feat(aircoding): AirCoding V2 baseline — deterministic multi-agent architecture

Forked from OpenCode v1.17.4 with multi-agent system:
- 5 agents: aircoding, scheduler, worker, architect, reviewer
- Deterministic DAG scheduling engine (coordinator_tick)
- Tool whitelists as hard enforcement
- AirCoding validation plugin
- System prompt injection for routing
- V1 requirements: C4 docs, ADR, AGENTS.md, debug-log.md
- Design documents in docs/

packages/app/src/components/prompt-input/attachments.test.ts

@@ -0,0 +1,108 @@
+import { describe, expect, test } from "bun:test"
+import { attachmentMime, pickAttachmentFiles } from "./files"
+import { pasteMode } from "./paste"
+
+describe("attachmentMime", () => {
+  test("keeps PDFs when the browser reports the mime", async () => {
+    const file = new File(["%PDF-1.7"], "guide.pdf", { type: "application/pdf" })
+    expect(await attachmentMime(file)).toBe("application/pdf")
+  })
+
+  test("normalizes structured text types to text/plain", async () => {
+    const file = new File(['{"ok":true}\n'], "data.json", { type: "application/json" })
+    expect(await attachmentMime(file)).toBe("text/plain")
+  })
+
+  test("accepts text files even with a misleading browser mime", async () => {
+    const file = new File(["export const x = 1\n"], "main.ts", { type: "video/mp2t" })
+    expect(await attachmentMime(file)).toBe("text/plain")
+  })
+
+  test("rejects binary files", async () => {
+    const file = new File([Uint8Array.of(0, 255, 1, 2)], "blob.bin", { type: "application/octet-stream" })
+    expect(await attachmentMime(file)).toBeUndefined()
+  })
+})
+
+describe("pickAttachmentFiles", () => {
+  test("reads the current project directory for every native picker invocation", async () => {
+    const paths: string[] = []
+    const files: File[] = []
+    const file = new File(["hello"], "hello.txt", { type: "text/plain" })
+    let directory = "C:\\Projects\\LoremIpsum"
+    const picker = async (options?: { defaultPath?: string }, onFile?: (file: File) => Promise<unknown>) => {
+      paths.push(options?.defaultPath ?? "")
+      await onFile?.(file)
+    }
+
+    pickAttachmentFiles({
+      picker,
+      directory: () => directory,
+      fallback: () => undefined,
+      onFile: async (selected) => files.push(selected),
+      onError: () => undefined,
+    })
+    await Promise.resolve()
+    directory = "C:\\Projects\\DolorSit"
+    pickAttachmentFiles({
+      picker,
+      directory: () => directory,
+      fallback: () => undefined,
+      onFile: async (selected) => files.push(selected),
+      onError: () => undefined,
+    })
+    await Promise.resolve()
+    expect(files).toEqual([file, file])
+    expect(paths).toEqual(["C:\\Projects\\LoremIpsum", "C:\\Projects\\DolorSit"])
+  })
+
+  test("uses the browser file input when no native picker exists", async () => {
+    let fallback = 0
+    pickAttachmentFiles({
+      directory: () => "/projects/consectetur-adipiscing",
+      fallback: () => {
+        fallback += 1
+      },
+      onFile: async () => undefined,
+      onError: () => undefined,
+    })
+    expect(fallback).toBe(1)
+  })
+
+  test("reports native picker failures without rejecting", async () => {
+    const error = new Error("picker unavailable")
+    const errors: unknown[] = []
+    const handled = Promise.withResolvers<void>()
+    pickAttachmentFiles({
+      picker: async () => Promise.reject(error),
+      directory: () => "C:\\Projects\\LoremIpsum",
+      fallback: () => undefined,
+      onFile: async () => undefined,
+      onError: (cause) => {
+        errors.push(cause)
+        handled.resolve()
+      },
+    })
+    await handled.promise
+    expect(errors).toEqual([error])
+  })
+})
+
+describe("pasteMode", () => {
+  test("uses native paste for short single-line text", () => {
+    expect(pasteMode("hello world")).toBe("native")
+  })
+
+  test("uses manual paste for multiline text", () => {
+    expect(
+      pasteMode(`{
+  "ok": true
+}`),
+    ).toBe("manual")
+    expect(pasteMode("a\r\nb")).toBe("manual")
+  })
+
+  test("uses manual paste for large text", () => {
+    expect(pasteMode("x".repeat(8000))).toBe("manual")
+  })
+})

packages/app/src/components/prompt-input/attachments.ts

@@ -0,0 +1,196 @@
+import { onMount } from "solid-js"
+import { makeEventListener } from "@solid-primitives/event-listener"
+import { showToast } from "@/utils/toast"
+import { usePrompt, type ContentPart, type ImageAttachmentPart } from "@/context/prompt"
+import { useLanguage } from "@/context/language"
+import { uuid } from "@/utils/uuid"
+import { getCursorPosition } from "./editor-dom"
+import { attachmentMime } from "./files"
+import { normalizePaste, pasteMode } from "./paste"
+
+function dataUrl(file: File, mime: string) {
+  return new Promise<string>((resolve) => {
+    const reader = new FileReader()
+    reader.addEventListener("error", () => resolve(""))
+    reader.addEventListener("load", () => {
+      const value = typeof reader.result === "string" ? reader.result : ""
+      const idx = value.indexOf(",")
+      if (idx === -1) {
+        resolve(value)
+        return
+      }
+      resolve(`data:${mime};base64,${value.slice(idx + 1)}`)
+    })
+    reader.readAsDataURL(file)
+  })
+}
+
+type PromptAttachmentsInput = {
+  editor: () => HTMLDivElement | undefined
+  isDialogActive: () => boolean
+  setDraggingType: (type: "image" | "@mention" | null) => void
+  focusEditor: () => void
+  addPart: (part: ContentPart) => boolean
+  readClipboardImage?: () => Promise<File | null>
+}
+
+export function createPromptAttachments(input: PromptAttachmentsInput) {
+  const prompt = usePrompt()
+  const language = useLanguage()
+
+  const warn = () => {
+    showToast({
+      title: language.t("prompt.toast.pasteUnsupported.title"),
+      description: language.t("prompt.toast.pasteUnsupported.description"),
+    })
+  }
+
+  const add = async (file: File, toast = true) => {
+    const mime = await attachmentMime(file)
+    if (!mime) {
+      if (toast) warn()
+      return false
+    }
+
+    const editor = input.editor()
+    if (!editor) return false
+
+    const url = await dataUrl(file, mime)
+    if (!url) return false
+
+    const attachment: ImageAttachmentPart = {
+      type: "image",
+      id: uuid(),
+      filename: file.name,
+      mime,
+      dataUrl: url,
+    }
+    const cursor = prompt.cursor() ?? getCursorPosition(editor)
+    prompt.set([...prompt.current(), attachment], cursor)
+    return true
+  }
+
+  const addAttachment = (file: File) => add(file)
+
+  const addAttachments = async (files: File[], toast = true) => {
+    let found = false
+
+    for (const file of files) {
+      const ok = await add(file, false)
+      if (ok) found = true
+    }
+
+    if (!found && files.length > 0 && toast) warn()
+    return found
+  }
+
+  const removeAttachment = (id: string) => {
+    const current = prompt.current()
+    const next = current.filter((part) => part.type !== "image" || part.id !== id)
+    prompt.set(next, prompt.cursor())
+  }
+
+  const handlePaste = async (event: ClipboardEvent) => {
+    const clipboardData = event.clipboardData
+    if (!clipboardData) return
+
+    event.preventDefault()
+    event.stopPropagation()
+
+    const files = Array.from(clipboardData.items).flatMap((item) => {
+      if (item.kind !== "file") return []
+      const file = item.getAsFile()
+      return file ? [file] : []
+    })
+
+    if (files.length > 0) {
+      await addAttachments(files)
+      return
+    }
+
+    const plainText = clipboardData.getData("text/plain") ?? ""
+
+    // Desktop: Browser clipboard has no images and no text, try platform's native clipboard for images
+    if (input.readClipboardImage && !plainText) {
+      const file = await input.readClipboardImage()
+      if (file) {
+        await addAttachment(file)
+        return
+      }
+    }
+
+    if (!plainText) return
+
+    const text = normalizePaste(plainText)
+
+    const put = () => {
+      if (input.addPart({ type: "text", content: text, start: 0, end: 0 })) return true
+      input.focusEditor()
+      return input.addPart({ type: "text", content: text, start: 0, end: 0 })
+    }
+
+    if (pasteMode(text) === "manual") {
+      put()
+      return
+    }
+
+    const inserted = typeof document.execCommand === "function" && document.execCommand("insertText", false, text)
+    if (inserted) return
+
+    put()
+  }
+
+  const handleGlobalDragOver = (event: DragEvent) => {
+    if (input.isDialogActive()) return
+
+    event.preventDefault()
+    const hasFiles = event.dataTransfer?.types.includes("Files")
+    const hasText = event.dataTransfer?.types.includes("text/plain")
+    if (hasFiles) {
+      input.setDraggingType("image")
+    } else if (hasText) {
+      input.setDraggingType("@mention")
+    }
+  }
+
+  const handleGlobalDragLeave = (event: DragEvent) => {
+    if (input.isDialogActive()) return
+    if (!event.relatedTarget) {
+      input.setDraggingType(null)
+    }
+  }
+
+  const handleGlobalDrop = async (event: DragEvent) => {
+    if (input.isDialogActive()) return
+
+    event.preventDefault()
+    input.setDraggingType(null)
+
+    const plainText = event.dataTransfer?.getData("text/plain")
+    const filePrefix = "file:"
+    if (plainText?.startsWith(filePrefix)) {
+      const filePath = plainText.slice(filePrefix.length)
+      input.focusEditor()
+      input.addPart({ type: "file", path: filePath, content: "@" + filePath, start: 0, end: 0 })
+      return
+    }
+
+    const dropped = event.dataTransfer?.files
+    if (!dropped) return
+
+    await addAttachments(Array.from(dropped))
+  }
+
+  onMount(() => {
+    makeEventListener(document, "dragover", handleGlobalDragOver)
+    makeEventListener(document, "dragleave", handleGlobalDragLeave)
+    makeEventListener(document, "drop", handleGlobalDrop)
+  })
+
+  return {
+    addAttachment,
+    addAttachments,
+    removeAttachment,
+    handlePaste,
+  }
+}

packages/app/src/components/prompt-input/build-request-parts.test.ts

@@ -0,0 +1,336 @@
+import { describe, expect, test } from "bun:test"
+import type { Prompt } from "@/context/prompt"
+import { buildRequestParts } from "./build-request-parts"
+
+describe("buildRequestParts", () => {
+  test("builds typed request and optimistic parts without cast path", () => {
+    const prompt: Prompt = [
+      { type: "text", content: "hello", start: 0, end: 5 },
+      {
+        type: "file",
+        path: "src/foo.ts",
+        content: "@src/foo.ts",
+        start: 5,
+        end: 16,
+        selection: { startLine: 4, startChar: 1, endLine: 6, endChar: 1 },
+      },
+      { type: "agent", name: "planner", content: "@planner", start: 16, end: 24 },
+    ]
+
+    const result = buildRequestParts({
+      prompt,
+      context: [{ key: "ctx:1", type: "file", path: "src/bar.ts", comment: "check this" }],
+      images: [
+        { type: "image", id: "img_1", filename: "a.png", mime: "image/png", dataUrl: "data:image/png;base64,AAA" },
+      ],
+      text: "hello @src/foo.ts @planner",
+      messageID: "msg_1",
+      sessionID: "ses_1",
+      sessionDirectory: "/repo",
+    })
+
+    expect(result.requestParts[0]?.type).toBe("text")
+    expect(result.requestParts.some((part) => part.type === "agent")).toBe(true)
+    expect(
+      result.requestParts.some((part) => part.type === "file" && part.url.startsWith("file:///repo/src/foo.ts")),
+    ).toBe(true)
+    expect(result.requestParts.some((part) => part.type === "text" && part.synthetic)).toBe(true)
+    expect(
+      result.requestParts.some(
+        (part) =>
+          part.type === "text" &&
+          part.synthetic &&
+          part.metadata?.opencodeComment &&
+          (part.metadata.opencodeComment as { comment?: string }).comment === "check this",
+      ),
+    ).toBe(true)
+
+    expect(result.optimisticParts).toHaveLength(result.requestParts.length)
+    expect(result.optimisticParts.every((part) => part.sessionID === "ses_1" && part.messageID === "msg_1")).toBe(true)
+  })
+
+  test("keeps multiple uploaded attachments in order", () => {
+    const result = buildRequestParts({
+      prompt: [{ type: "text", content: "check these", start: 0, end: 11 }],
+      context: [],
+      images: [
+        { type: "image", id: "img_1", filename: "a.png", mime: "image/png", dataUrl: "data:image/png;base64,AAA" },
+        {
+          type: "image",
+          id: "img_2",
+          filename: "b.pdf",
+          mime: "application/pdf",
+          dataUrl: "data:application/pdf;base64,BBB",
+        },
+      ],
+      text: "check these",
+      messageID: "msg_multi",
+      sessionID: "ses_multi",
+      sessionDirectory: "/repo",
+    })
+
+    const files = result.requestParts.filter((part) => part.type === "file" && part.url.startsWith("data:"))
+
+    expect(files).toHaveLength(2)
+    expect(files.map((part) => (part.type === "file" ? part.filename : ""))).toEqual(["a.png", "b.pdf"])
+  })
+
+  test("deduplicates context files when prompt already includes same path", () => {
+    const prompt: Prompt = [{ type: "file", path: "src/foo.ts", content: "@src/foo.ts", start: 0, end: 11 }]
+
+    const result = buildRequestParts({
+      prompt,
+      context: [
+        { key: "ctx:dup", type: "file", path: "src/foo.ts" },
+        { key: "ctx:comment", type: "file", path: "src/foo.ts", comment: "focus here" },
+      ],
+      images: [],
+      text: "@src/foo.ts",
+      messageID: "msg_2",
+      sessionID: "ses_2",
+      sessionDirectory: "/repo",
+    })
+
+    const fooFiles = result.requestParts.filter(
+      (part) => part.type === "file" && part.url.startsWith("file:///repo/src/foo.ts"),
+    )
+    const synthetic = result.requestParts.filter((part) => part.type === "text" && part.synthetic)
+
+    expect(fooFiles).toHaveLength(2)
+    expect(synthetic).toHaveLength(1)
+  })
+
+  test("adds file parts for @mentions inside comment text", () => {
+    const result = buildRequestParts({
+      prompt: [{ type: "text", content: "look", start: 0, end: 4 }],
+      context: [
+        {
+          key: "ctx:comment-mention",
+          type: "file",
+          path: "src/review.ts",
+          comment: "Compare with @src/shared.ts and @src/review.ts.",
+        },
+      ],
+      images: [],
+      text: "look",
+      messageID: "msg_comment_mentions",
+      sessionID: "ses_comment_mentions",
+      sessionDirectory: "/repo",
+    })
+
+    const files = result.requestParts.filter((part) => part.type === "file")
+    expect(files).toHaveLength(2)
+    expect(files.some((part) => part.type === "file" && part.url === "file:///repo/src/review.ts")).toBe(true)
+    expect(files.some((part) => part.type === "file" && part.url === "file:///repo/src/shared.ts")).toBe(true)
+  })
+
+  test("handles Windows paths correctly (simulated on macOS)", () => {
+    const prompt: Prompt = [{ type: "file", path: "src\\foo.ts", content: "@src\\foo.ts", start: 0, end: 11 }]
+
+    const result = buildRequestParts({
+      prompt,
+      context: [],
+      images: [],
+      text: "@src\\foo.ts",
+      messageID: "msg_win_1",
+      sessionID: "ses_win_1",
+      sessionDirectory: "D:\\projects\\myapp", // Windows path
+    })
+
+    // Should create valid file URLs
+    const filePart = result.requestParts.find((part) => part.type === "file")
+    expect(filePart).toBeDefined()
+    if (filePart?.type === "file") {
+      // URL should be parseable
+      expect(() => new URL(filePart.url)).not.toThrow()
+      // Should not have encoded backslashes in wrong place
+      expect(filePart.url).not.toContain("%5C")
+      // Should have normalized to forward slashes
+      expect(filePart.url).toContain("/src/foo.ts")
+    }
+  })
+
+  test("handles Windows absolute path with special characters", () => {
+    const prompt: Prompt = [{ type: "file", path: "file#name.txt", content: "@file#name.txt", start: 0, end: 14 }]
+
+    const result = buildRequestParts({
+      prompt,
+      context: [],
+      images: [],
+      text: "@file#name.txt",
+      messageID: "msg_win_2",
+      sessionID: "ses_win_2",
+      sessionDirectory: "C:\\Users\\test\\Documents", // Windows path
+    })
+
+    const filePart = result.requestParts.find((part) => part.type === "file")
+    expect(filePart).toBeDefined()
+    if (filePart?.type === "file") {
+      // URL should be parseable
+      expect(() => new URL(filePart.url)).not.toThrow()
+      // Special chars should be encoded
+      expect(filePart.url).toContain("file%23name.txt")
+      // Should have Windows drive letter properly encoded
+      expect(filePart.url).toMatch(/file:\/\/\/[A-Z]:/)
+    }
+  })
+
+  test("handles Linux absolute paths correctly", () => {
+    const prompt: Prompt = [{ type: "file", path: "src/app.ts", content: "@src/app.ts", start: 0, end: 10 }]
+
+    const result = buildRequestParts({
+      prompt,
+      context: [],
+      images: [],
+      text: "@src/app.ts",
+      messageID: "msg_linux_1",
+      sessionID: "ses_linux_1",
+      sessionDirectory: "/home/user/project",
+    })
+
+    const filePart = result.requestParts.find((part) => part.type === "file")
+    expect(filePart).toBeDefined()
+    if (filePart?.type === "file") {
+      // URL should be parseable
+      expect(() => new URL(filePart.url)).not.toThrow()
+      // Should be a normal Unix path
+      expect(filePart.url).toBe("file:///home/user/project/src/app.ts")
+    }
+  })
+
+  test("handles macOS paths correctly", () => {
+    const prompt: Prompt = [{ type: "file", path: "README.md", content: "@README.md", start: 0, end: 9 }]
+
+    const result = buildRequestParts({
+      prompt,
+      context: [],
+      images: [],
+      text: "@README.md",
+      messageID: "msg_mac_1",
+      sessionID: "ses_mac_1",
+      sessionDirectory: "/Users/kelvin/Projects/opencode",
+    })
+
+    const filePart = result.requestParts.find((part) => part.type === "file")
+    expect(filePart).toBeDefined()
+    if (filePart?.type === "file") {
+      // URL should be parseable
+      expect(() => new URL(filePart.url)).not.toThrow()
+      // Should be a normal Unix path
+      expect(filePart.url).toBe("file:///Users/kelvin/Projects/opencode/README.md")
+    }
+  })
+
+  test("handles context files with Windows paths", () => {
+    const prompt: Prompt = []
+
+    const result = buildRequestParts({
+      prompt,
+      context: [
+        { key: "ctx:1", type: "file", path: "src\\utils\\helper.ts" },
+        { key: "ctx:2", type: "file", path: "test\\unit.test.ts", comment: "check tests" },
+      ],
+      images: [],
+      text: "test",
+      messageID: "msg_win_ctx",
+      sessionID: "ses_win_ctx",
+      sessionDirectory: "D:\\workspace\\app",
+    })
+
+    const fileParts = result.requestParts.filter((part) => part.type === "file")
+    expect(fileParts).toHaveLength(2)
+
+    // All file URLs should be valid
+    fileParts.forEach((part) => {
+      if (part.type === "file") {
+        expect(() => new URL(part.url)).not.toThrow()
+        expect(part.url).not.toContain("%5C") // No encoded backslashes
+      }
+    })
+  })
+
+  test("handles absolute Windows paths (user manually specifies full path)", () => {
+    const prompt: Prompt = [
+      { type: "file", path: "D:\\other\\project\\file.ts", content: "@D:\\other\\project\\file.ts", start: 0, end: 25 },
+    ]
+
+    const result = buildRequestParts({
+      prompt,
+      context: [],
+      images: [],
+      text: "@D:\\other\\project\\file.ts",
+      messageID: "msg_abs",
+      sessionID: "ses_abs",
+      sessionDirectory: "C:\\current\\project",
+    })
+
+    const filePart = result.requestParts.find((part) => part.type === "file")
+    expect(filePart).toBeDefined()
+    if (filePart?.type === "file") {
+      // Should handle absolute path that differs from sessionDirectory
+      expect(() => new URL(filePart.url)).not.toThrow()
+      expect(filePart.url).toContain("/D:/other/project/file.ts")
+    }
+  })
+
+  test("handles selection with query parameters on Windows", () => {
+    const prompt: Prompt = [
+      {
+        type: "file",
+        path: "src\\App.tsx",
+        content: "@src\\App.tsx",
+        start: 0,
+        end: 11,
+        selection: { startLine: 10, startChar: 0, endLine: 20, endChar: 5 },
+      },
+    ]
+
+    const result = buildRequestParts({
+      prompt,
+      context: [],
+      images: [],
+      text: "@src\\App.tsx",
+      messageID: "msg_sel",
+      sessionID: "ses_sel",
+      sessionDirectory: "C:\\project",
+    })
+
+    const filePart = result.requestParts.find((part) => part.type === "file")
+    expect(filePart).toBeDefined()
+    if (filePart?.type === "file") {
+      // Should have query parameters
+      expect(filePart.url).toContain("?start=10&end=20")
+      // Should be valid URL
+      expect(() => new URL(filePart.url)).not.toThrow()
+      // Query params should parse correctly
+      const url = new URL(filePart.url)
+      expect(url.searchParams.get("start")).toBe("10")
+      expect(url.searchParams.get("end")).toBe("20")
+    }
+  })
+
+  test("handles file paths with dots and special segments on Windows", () => {
+    const prompt: Prompt = [
+      { type: "file", path: "..\\..\\shared\\util.ts", content: "@..\\..\\shared\\util.ts", start: 0, end: 21 },
+    ]
+
+    const result = buildRequestParts({
+      prompt,
+      context: [],
+      images: [],
+      text: "@..\\..\\shared\\util.ts",
+      messageID: "msg_dots",
+      sessionID: "ses_dots",
+      sessionDirectory: "C:\\projects\\myapp\\src",
+    })
+
+    const filePart = result.requestParts.find((part) => part.type === "file")
+    expect(filePart).toBeDefined()
+    if (filePart?.type === "file") {
+      // Should be valid URL
+      expect(() => new URL(filePart.url)).not.toThrow()
+      // Should preserve .. segments (backend normalizes)
+      expect(filePart.url).toContain("/..")
+    }
+  })
+})

packages/app/src/components/prompt-input/build-request-parts.ts

@@ -0,0 +1,201 @@
+import { getFilename } from "@opencode-ai/core/util/path"
+import { type AgentPartInput, type FilePartInput, type Part, type TextPartInput } from "@opencode-ai/sdk/v2/client"
+import type { FileSelection } from "@/context/file"
+import { encodeFilePath } from "@/context/file/path"
+import type { AgentPart, FileAttachmentPart, ImageAttachmentPart, Prompt } from "@/context/prompt"
+import { Identifier } from "@/utils/id"
+import { createCommentMetadata, formatCommentNote } from "@/utils/comment-note"
+
+type PromptRequestPart = (TextPartInput | FilePartInput | AgentPartInput) & { id: string }
+
+type ContextFile = {
+  key: string
+  type: "file"
+  path: string
+  selection?: FileSelection
+  comment?: string
+  commentID?: string
+  commentOrigin?: "review" | "file"
+  preview?: string
+}
+
+type BuildRequestPartsInput = {
+  prompt: Prompt
+  context: ContextFile[]
+  images: ImageAttachmentPart[]
+  text: string
+  messageID: string
+  sessionID: string
+  sessionDirectory: string
+}
+
+const absolute = (directory: string, path: string) => {
+  if (path.startsWith("/")) return path
+  if (/^[A-Za-z]:[\\/]/.test(path) || /^[A-Za-z]:$/.test(path)) return path
+  if (path.startsWith("\\\\") || path.startsWith("//")) return path
+  return `${directory.replace(/[\\/]+$/, "")}/${path}`
+}
+
+const fileQuery = (selection: FileSelection | undefined) =>
+  selection ? `?start=${selection.startLine}&end=${selection.endLine}` : ""
+
+const mention = /(^|[\s([{"'])@(\S+)/g
+
+const parseCommentMentions = (comment: string) => {
+  return Array.from(comment.matchAll(mention)).flatMap((match) => {
+    const path = (match[2] ?? "").replace(/[.,!?;:)}\]"']+$/, "")
+    if (!path) return []
+    return [path]
+  })
+}
+
+const isFileAttachment = (part: Prompt[number]): part is FileAttachmentPart => part.type === "file"
+const isAgentAttachment = (part: Prompt[number]): part is AgentPart => part.type === "agent"
+
+const toOptimisticPart = (part: PromptRequestPart, sessionID: string, messageID: string): Part => {
+  if (part.type === "text") {
+    return {
+      id: part.id,
+      type: "text",
+      text: part.text,
+      synthetic: part.synthetic,
+      ignored: part.ignored,
+      time: part.time,
+      metadata: part.metadata,
+      sessionID,
+      messageID,
+    }
+  }
+  if (part.type === "file") {
+    return {
+      id: part.id,
+      type: "file",
+      mime: part.mime,
+      filename: part.filename,
+      url: part.url,
+      source: part.source,
+      sessionID,
+      messageID,
+    }
+  }
+  return {
+    id: part.id,
+    type: "agent",
+    name: part.name,
+    source: part.source,
+    sessionID,
+    messageID,
+  }
+}
+
+export function buildRequestParts(input: BuildRequestPartsInput) {
+  const requestParts: PromptRequestPart[] = [
+    {
+      id: Identifier.ascending("part"),
+      type: "text",
+      text: input.text,
+    },
+  ]
+
+  const files = input.prompt.filter(isFileAttachment).map((attachment) => {
+    const path = absolute(input.sessionDirectory, attachment.path)
+    return {
+      id: Identifier.ascending("part"),
+      type: "file",
+      mime: "text/plain",
+      url: `file://${encodeFilePath(path)}${fileQuery(attachment.selection)}`,
+      filename: getFilename(attachment.path),
+      source: {
+        type: "file",
+        text: {
+          value: attachment.content,
+          start: attachment.start,
+          end: attachment.end,
+        },
+        path,
+      },
+    } satisfies PromptRequestPart
+  })
+
+  const agents = input.prompt.filter(isAgentAttachment).map((attachment) => {
+    return {
+      id: Identifier.ascending("part"),
+      type: "agent",
+      name: attachment.name,
+      source: {
+        value: attachment.content,
+        start: attachment.start,
+        end: attachment.end,
+      },
+    } satisfies PromptRequestPart
+  })
+
+  const used = new Set(files.map((part) => part.url))
+  const context = input.context.flatMap((item) => {
+    const path = absolute(input.sessionDirectory, item.path)
+    const url = `file://${encodeFilePath(path)}${fileQuery(item.selection)}`
+    const comment = item.comment?.trim()
+    if (!comment && used.has(url)) return []
+    used.add(url)
+
+    const filePart = {
+      id: Identifier.ascending("part"),
+      type: "file",
+      mime: "text/plain",
+      url,
+      filename: getFilename(item.path),
+    } satisfies PromptRequestPart
+
+    if (!comment) return [filePart]
+
+    const mentions = parseCommentMentions(comment).flatMap((path) => {
+      const url = `file://${encodeFilePath(absolute(input.sessionDirectory, path))}`
+      if (used.has(url)) return []
+      used.add(url)
+      return [
+        {
+          id: Identifier.ascending("part"),
+          type: "file",
+          mime: "text/plain",
+          url,
+          filename: getFilename(path),
+        } satisfies PromptRequestPart,
+      ]
+    })
+
+    return [
+      {
+        id: Identifier.ascending("part"),
+        type: "text",
+        text: formatCommentNote({ path: item.path, selection: item.selection, comment }),
+        synthetic: true,
+        metadata: createCommentMetadata({
+          path: item.path,
+          selection: item.selection,
+          comment,
+          preview: item.preview,
+          origin: item.commentOrigin,
+        }),
+      } satisfies PromptRequestPart,
+      filePart,
+      ...mentions,
+    ]
+  })
+
+  const images = input.images.map((attachment) => {
+    return {
+      id: Identifier.ascending("part"),
+      type: "file",
+      mime: attachment.mime,
+      url: attachment.dataUrl,
+      filename: attachment.filename,
+    } satisfies PromptRequestPart
+  })
+
+  requestParts.push(...files, ...context, ...agents, ...images)
+
+  return {
+    requestParts,
+    optimisticParts: requestParts.map((part) => toOptimisticPart(part, input.sessionID, input.messageID)),
+  }
+}

packages/app/src/components/prompt-input/context-items.tsx

@@ -0,0 +1,88 @@
+import { Component, For, Show } from "solid-js"
+import { FileIcon } from "@opencode-ai/ui/file-icon"
+import { IconButton } from "@opencode-ai/ui/icon-button"
+import { Tooltip } from "@opencode-ai/ui/tooltip"
+import { getDirectory, getFilename, getFilenameTruncated } from "@opencode-ai/core/util/path"
+import type { ContextItem } from "@/context/prompt"
+
+type PromptContextItem = ContextItem & { key: string }
+
+type ContextItemsProps = {
+  items: PromptContextItem[]
+  active: (item: PromptContextItem) => boolean
+  openComment: (item: PromptContextItem) => void
+  remove: (item: PromptContextItem) => void
+  t: (key: string) => string
+}
+
+export const PromptContextItems: Component<ContextItemsProps> = (props) => {
+  return (
+    <Show when={props.items.length > 0}>
+      <div class="flex flex-nowrap items-start gap-2 p-2 overflow-x-auto no-scrollbar">
+        <For each={props.items}>
+          {(item) => {
+            const directory = getDirectory(item.path)
+            const filename = getFilename(item.path)
+            const label = getFilenameTruncated(item.path, 14)
+            const selected = props.active(item)
+
+            return (
+              <Tooltip
+                value={
+                  <span class="flex max-w-[300px]">
+                    <span class="text-text-invert-base truncate-start [unicode-bidi:plaintext] min-w-0">
+                      {directory}
+                    </span>
+                    <span class="shrink-0">{filename}</span>
+                  </span>
+                }
+                placement="top"
+                openDelay={2000}
+              >
+                <div
+                  classList={{
+                    "group shrink-0 flex flex-col rounded-[6px] pl-2 pr-1 py-1 max-w-[200px] h-12 cursor-default transition-all transition-transform shadow-xs-border hover:shadow-xs-border-hover": true,
+                    "hover:bg-surface-interactive-weak": !!item.commentID && !selected,
+                    "bg-surface-interactive-hover hover:bg-surface-interactive-hover shadow-xs-border-hover": selected,
+                    "bg-background-stronger": !selected,
+                  }}
+                  onClick={() => props.openComment(item)}
+                >
+                  <div class="flex items-center gap-1.5">
+                    <FileIcon node={{ path: item.path, type: "file" }} class="shrink-0 size-3.5" />
+                    <div class="flex items-center text-11-regular min-w-0 font-medium">
+                      <span class="text-text-strong whitespace-nowrap">{label}</span>
+                      <Show when={item.selection}>
+                        {(sel) => (
+                          <span class="text-text-weak whitespace-nowrap shrink-0">
+                            {sel().startLine === sel().endLine
+                              ? `:${sel().startLine}`
+                              : `:${sel().startLine}-${sel().endLine}`}
+                          </span>
+                        )}
+                      </Show>
+                    </div>
+                    <IconButton
+                      type="button"
+                      icon="close-small"
+                      variant="ghost"
+                      class="ml-auto size-3.5 text-text-weak hover:text-text-strong transition-all"
+                      onClick={(e) => {
+                        e.stopPropagation()
+                        props.remove(item)
+                      }}
+                      aria-label={props.t("prompt.context.removeFile")}
+                    />
+                  </div>
+                  <Show when={item.comment}>
+                    {(comment) => <div class="text-12-regular text-text-strong ml-5 pr-1 truncate">{comment()}</div>}
+                  </Show>
+                </div>
+              </Tooltip>
+            )
+          }}
+        </For>
+      </div>
+    </Show>
+  )
+}

packages/app/src/components/prompt-input/drag-overlay.tsx

@@ -0,0 +1,25 @@
+import { Component, Show } from "solid-js"
+import { Icon } from "@opencode-ai/ui/icon"
+
+type PromptDragOverlayProps = {
+  type: "image" | "@mention" | null
+  label: string
+}
+
+const kindToIcon = {
+  image: "photo",
+  "@mention": "link",
+} as const
+
+export const PromptDragOverlay: Component<PromptDragOverlayProps> = (props) => {
+  return (
+    <Show when={props.type !== null}>
+      <div class="absolute inset-0 z-10 flex items-center justify-center bg-surface-raised-stronger-non-alpha/90 pointer-events-none">
+        <div class="flex flex-col items-center gap-2 text-text-weak">
+          <Icon name={props.type ? kindToIcon[props.type] : kindToIcon.image} class="size-8" />
+          <span class="text-14-regular">{props.label}</span>
+        </div>
+      </div>
+    </Show>
+  )
+}

packages/app/src/components/prompt-input/editor-dom.test.ts

@@ -0,0 +1,99 @@
+import { describe, expect, test } from "bun:test"
+import { createTextFragment, getCursorPosition, getNodeLength, getTextLength, setCursorPosition } from "./editor-dom"
+
+describe("prompt-input editor dom", () => {
+  test("createTextFragment preserves newlines with consecutive br nodes", () => {
+    const fragment = createTextFragment("foo\n\nbar")
+    const container = document.createElement("div")
+    container.appendChild(fragment)
+
+    expect(container.childNodes.length).toBe(4)
+    expect(container.childNodes[0]?.textContent).toBe("foo")
+    expect((container.childNodes[1] as HTMLElement).tagName).toBe("BR")
+    expect((container.childNodes[2] as HTMLElement).tagName).toBe("BR")
+    expect(container.childNodes[3]?.textContent).toBe("bar")
+  })
+
+  test("createTextFragment keeps trailing newline as terminal break", () => {
+    const fragment = createTextFragment("foo\n")
+    const container = document.createElement("div")
+    container.appendChild(fragment)
+
+    expect(container.childNodes.length).toBe(2)
+    expect(container.childNodes[0]?.textContent).toBe("foo")
+    expect((container.childNodes[1] as HTMLElement).tagName).toBe("BR")
+  })
+
+  test("createTextFragment avoids break-node explosion for large multiline content", () => {
+    const content = Array.from({ length: 220 }, () => "line").join("\n")
+    const fragment = createTextFragment(content)
+    const container = document.createElement("div")
+    container.appendChild(fragment)
+
+    expect(container.childNodes.length).toBe(1)
+    expect(container.childNodes[0]?.nodeType).toBe(Node.TEXT_NODE)
+    expect(container.textContent).toBe(content)
+  })
+
+  test("createTextFragment keeps terminal break in large multiline fallback", () => {
+    const content = `${Array.from({ length: 220 }, () => "line").join("\n")}\n`
+    const fragment = createTextFragment(content)
+    const container = document.createElement("div")
+    container.appendChild(fragment)
+
+    expect(container.childNodes.length).toBe(2)
+    expect(container.childNodes[0]?.textContent).toBe(content.slice(0, -1))
+    expect((container.childNodes[1] as HTMLElement).tagName).toBe("BR")
+  })
+
+  test("length helpers treat breaks as one char and ignore zero-width chars", () => {
+    const container = document.createElement("div")
+    container.appendChild(document.createTextNode("ab\u200B"))
+    container.appendChild(document.createElement("br"))
+    container.appendChild(document.createTextNode("cd"))
+
+    expect(getNodeLength(container.childNodes[0]!)).toBe(2)
+    expect(getNodeLength(container.childNodes[1]!)).toBe(1)
+    expect(getTextLength(container)).toBe(5)
+  })
+
+  test("setCursorPosition and getCursorPosition round-trip with pills and breaks", () => {
+    const container = document.createElement("div")
+    const pill = document.createElement("span")
+    pill.dataset.type = "file"
+    pill.textContent = "@file"
+    container.appendChild(document.createTextNode("ab"))
+    container.appendChild(pill)
+    container.appendChild(document.createElement("br"))
+    container.appendChild(document.createTextNode("cd"))
+    document.body.appendChild(container)
+
+    setCursorPosition(container, 2)
+    expect(getCursorPosition(container)).toBe(2)
+
+    setCursorPosition(container, 7)
+    expect(getCursorPosition(container)).toBe(7)
+
+    setCursorPosition(container, 8)
+    expect(getCursorPosition(container)).toBe(8)
+
+    container.remove()
+  })
+
+  test("setCursorPosition and getCursorPosition round-trip across blank lines", () => {
+    const container = document.createElement("div")
+    container.appendChild(document.createTextNode("a"))
+    container.appendChild(document.createElement("br"))
+    container.appendChild(document.createElement("br"))
+    container.appendChild(document.createTextNode("b"))
+    document.body.appendChild(container)
+
+    setCursorPosition(container, 2)
+    expect(getCursorPosition(container)).toBe(2)
+
+    setCursorPosition(container, 3)
+    expect(getCursorPosition(container)).toBe(3)
+
+    container.remove()
+  })
+})

packages/app/src/components/prompt-input/editor-dom.ts

@@ -0,0 +1,148 @@
+const MAX_BREAKS = 200
+
+export function createTextFragment(content: string): DocumentFragment {
+  const fragment = document.createDocumentFragment()
+  let breaks = 0
+  for (const char of content) {
+    if (char !== "\n") continue
+    breaks += 1
+    if (breaks > MAX_BREAKS) {
+      const tail = content.endsWith("\n")
+      const text = tail ? content.slice(0, -1) : content
+      if (text) fragment.appendChild(document.createTextNode(text))
+      if (tail) fragment.appendChild(document.createElement("br"))
+      return fragment
+    }
+  }
+
+  const segments = content.split("\n")
+  segments.forEach((segment, index) => {
+    if (segment) {
+      fragment.appendChild(document.createTextNode(segment))
+    }
+    if (index < segments.length - 1) {
+      fragment.appendChild(document.createElement("br"))
+    }
+  })
+  return fragment
+}
+
+export function getNodeLength(node: Node): number {
+  if (node.nodeType === Node.ELEMENT_NODE && (node as HTMLElement).tagName === "BR") return 1
+  return (node.textContent ?? "").replace(/\u200B/g, "").length
+}
+
+export function getTextLength(node: Node): number {
+  if (node.nodeType === Node.TEXT_NODE) return (node.textContent ?? "").replace(/\u200B/g, "").length
+  if (node.nodeType === Node.ELEMENT_NODE && (node as HTMLElement).tagName === "BR") return 1
+  let length = 0
+  for (const child of Array.from(node.childNodes)) {
+    length += getTextLength(child)
+  }
+  return length
+}
+
+export function getCursorPosition(parent: HTMLElement): number {
+  const selection = window.getSelection()
+  if (!selection || selection.rangeCount === 0) return 0
+  const range = selection.getRangeAt(0)
+  if (!parent.contains(range.startContainer)) return 0
+  const preCaretRange = range.cloneRange()
+  preCaretRange.selectNodeContents(parent)
+  preCaretRange.setEnd(range.startContainer, range.startOffset)
+  return getTextLength(preCaretRange.cloneContents())
+}
+
+export function setCursorPosition(parent: HTMLElement, position: number) {
+  let remaining = position
+  let node = parent.firstChild
+  while (node) {
+    const length = getNodeLength(node)
+    const isText = node.nodeType === Node.TEXT_NODE
+    const isPill =
+      node.nodeType === Node.ELEMENT_NODE &&
+      ((node as HTMLElement).dataset.type === "file" || (node as HTMLElement).dataset.type === "agent")
+    const isBreak = node.nodeType === Node.ELEMENT_NODE && (node as HTMLElement).tagName === "BR"
+
+    if (isText && remaining <= length) {
+      const range = document.createRange()
+      const selection = window.getSelection()
+      range.setStart(node, remaining)
+      range.collapse(true)
+      selection?.removeAllRanges()
+      selection?.addRange(range)
+      return
+    }
+
+    if ((isPill || isBreak) && remaining <= length) {
+      const range = document.createRange()
+      const selection = window.getSelection()
+      if (remaining === 0) {
+        range.setStartBefore(node)
+      }
+      if (remaining > 0 && isPill) {
+        range.setStartAfter(node)
+      }
+      if (remaining > 0 && isBreak) {
+        const next = node.nextSibling
+        if (next && next.nodeType === Node.TEXT_NODE) {
+          range.setStart(next, 0)
+        }
+        if (!next || next.nodeType !== Node.TEXT_NODE) {
+          range.setStartAfter(node)
+        }
+      }
+      range.collapse(true)
+      selection?.removeAllRanges()
+      selection?.addRange(range)
+      return
+    }
+
+    remaining -= length
+    node = node.nextSibling
+  }
+
+  const fallbackRange = document.createRange()
+  const fallbackSelection = window.getSelection()
+  const last = parent.lastChild
+  if (last && last.nodeType === Node.TEXT_NODE) {
+    const len = last.textContent ? last.textContent.length : 0
+    fallbackRange.setStart(last, len)
+  }
+  if (!last || last.nodeType !== Node.TEXT_NODE) {
+    fallbackRange.selectNodeContents(parent)
+  }
+  fallbackRange.collapse(false)
+  fallbackSelection?.removeAllRanges()
+  fallbackSelection?.addRange(fallbackRange)
+}
+
+export function setRangeEdge(parent: HTMLElement, range: Range, edge: "start" | "end", offset: number) {
+  let remaining = offset
+  const nodes = Array.from(parent.childNodes)
+
+  for (const node of nodes) {
+    const length = getNodeLength(node)
+    const isText = node.nodeType === Node.TEXT_NODE
+    const isPill =
+      node.nodeType === Node.ELEMENT_NODE &&
+      ((node as HTMLElement).dataset.type === "file" || (node as HTMLElement).dataset.type === "agent")
+    const isBreak = node.nodeType === Node.ELEMENT_NODE && (node as HTMLElement).tagName === "BR"
+
+    if (isText && remaining <= length) {
+      if (edge === "start") range.setStart(node, remaining)
+      if (edge === "end") range.setEnd(node, remaining)
+      return
+    }
+
+    if ((isPill || isBreak) && remaining <= length) {
+      if (edge === "start" && remaining === 0) range.setStartBefore(node)
+      if (edge === "start" && remaining > 0) range.setStartAfter(node)
+      if (edge === "end" && remaining === 0) range.setEndBefore(node)
+      if (edge === "end" && remaining > 0) range.setEndAfter(node)
+      return
+    }
+
+    remaining -= length
+  }
+}

packages/app/src/components/prompt-input/files.ts

@@ -0,0 +1,98 @@
+import { ACCEPTED_FILE_TYPES, ACCEPTED_IMAGE_TYPES } from "@/constants/file-picker"
+
+export { ACCEPTED_FILE_TYPES }
+
+type AttachmentPicker = (
+  options: {
+    defaultPath?: string
+    multiple?: boolean
+    accept?: string[]
+  },
+  onFile: (file: File) => Promise<unknown>,
+) => Promise<void>
+
+export function pickAttachmentFiles(input: {
+  picker?: AttachmentPicker
+  directory: () => string
+  fallback: () => void
+  onFile: (file: File) => Promise<unknown>
+  onError: (error: unknown) => void
+}) {
+  if (!input.picker) {
+    input.fallback()
+    return
+  }
+  void input
+    .picker(
+      {
+        defaultPath: input.directory(),
+        multiple: true,
+        accept: ACCEPTED_FILE_TYPES,
+      },
+      input.onFile,
+    )
+    .catch(input.onError)
+}
+
+const IMAGE_MIMES = new Set(ACCEPTED_IMAGE_TYPES)
+const IMAGE_EXTS = new Map([
+  ["gif", "image/gif"],
+  ["jpeg", "image/jpeg"],
+  ["jpg", "image/jpeg"],
+  ["png", "image/png"],
+  ["webp", "image/webp"],
+])
+const TEXT_MIMES = new Set([
+  "application/json",
+  "application/ld+json",
+  "application/toml",
+  "application/x-toml",
+  "application/x-yaml",
+  "application/xml",
+  "application/yaml",
+])
+
+const SAMPLE = 4096
+
+function kind(type: string) {
+  return type.split(";", 1)[0]?.trim().toLowerCase() ?? ""
+}
+
+function ext(name: string) {
+  const idx = name.lastIndexOf(".")
+  if (idx === -1) return ""
+  return name.slice(idx + 1).toLowerCase()
+}
+
+function textMime(type: string) {
+  if (!type) return false
+  if (type.startsWith("text/")) return true
+  if (TEXT_MIMES.has(type)) return true
+  if (type.endsWith("+json")) return true
+  return type.endsWith("+xml")
+}
+
+function textBytes(bytes: Uint8Array) {
+  if (bytes.length === 0) return true
+  let count = 0
+  for (const byte of bytes) {
+    if (byte === 0) return false
+    if (byte < 9 || (byte > 13 && byte < 32)) count += 1
+  }
+  return count / bytes.length <= 0.3
+}
+
+export async function attachmentMime(file: File) {
+  const type = kind(file.type)
+  if (IMAGE_MIMES.has(type)) return type
+  if (type === "application/pdf") return type
+
+  const suffix = ext(file.name)
+  const fallback = IMAGE_EXTS.get(suffix) ?? (suffix === "pdf" ? "application/pdf" : undefined)
+  if ((!type || type === "application/octet-stream") && fallback) return fallback
+
+  if (textMime(type)) return "text/plain"
+  const bytes = new Uint8Array(await file.slice(0, SAMPLE).arrayBuffer())
+  if (!textBytes(bytes)) return
+  return "text/plain"
+}

packages/app/src/components/prompt-input/history.test.ts

@@ -0,0 +1,153 @@
+import { describe, expect, test } from "bun:test"
+import type { Prompt } from "@/context/prompt"
+import {
+  canNavigateHistoryAtCursor,
+  clonePromptParts,
+  normalizePromptHistoryEntry,
+  navigatePromptHistory,
+  prependHistoryEntry,
+  promptLength,
+  type PromptHistoryComment,
+} from "./history"
+
+const DEFAULT_PROMPT: Prompt = [{ type: "text", content: "", start: 0, end: 0 }]
+
+const text = (value: string): Prompt => [{ type: "text", content: value, start: 0, end: value.length }]
+const comment = (id: string, value = "note"): PromptHistoryComment => ({
+  id,
+  path: "src/a.ts",
+  selection: { start: 2, end: 4 },
+  comment: value,
+  time: 1,
+  origin: "review",
+  preview: "const a = 1",
+})
+
+describe("prompt-input history", () => {
+  test("prependHistoryEntry skips empty prompt and deduplicates consecutive entries", () => {
+    const first = prependHistoryEntry([], DEFAULT_PROMPT)
+    expect(first).toEqual([])
+
+    const commentsOnly = prependHistoryEntry([], DEFAULT_PROMPT, [comment("c1")])
+    expect(commentsOnly).toHaveLength(1)
+
+    const withOne = prependHistoryEntry([], text("hello"))
+    expect(withOne).toHaveLength(1)
+
+    const deduped = prependHistoryEntry(withOne, text("hello"))
+    expect(deduped).toBe(withOne)
+
+    const dedupedComments = prependHistoryEntry(commentsOnly, DEFAULT_PROMPT, [comment("c1")])
+    expect(dedupedComments).toBe(commentsOnly)
+  })
+
+  test("navigatePromptHistory restores saved prompt when moving down from newest", () => {
+    const entries = [text("third"), text("second"), text("first")]
+    const up = navigatePromptHistory({
+      direction: "up",
+      entries,
+      historyIndex: -1,
+      currentPrompt: text("draft"),
+      currentComments: [comment("draft")],
+      savedPrompt: null,
+    })
+    expect(up.handled).toBe(true)
+    if (!up.handled) throw new Error("expected handled")
+    expect(up.historyIndex).toBe(0)
+    expect(up.cursor).toBe("start")
+    expect(up.entry.comments).toEqual([])
+
+    const down = navigatePromptHistory({
+      direction: "down",
+      entries,
+      historyIndex: up.historyIndex,
+      currentPrompt: text("ignored"),
+      currentComments: [],
+      savedPrompt: up.savedPrompt,
+    })
+    expect(down.handled).toBe(true)
+    if (!down.handled) throw new Error("expected handled")
+    expect(down.historyIndex).toBe(-1)
+    expect(down.entry.prompt[0]?.type === "text" ? down.entry.prompt[0].content : "").toBe("draft")
+    expect(down.entry.comments).toEqual([comment("draft")])
+  })
+
+  test("navigatePromptHistory keeps entry comments when moving through history", () => {
+    const entries = [
+      {
+        prompt: text("with comment"),
+        comments: [comment("c1")],
+      },
+    ]
+
+    const up = navigatePromptHistory({
+      direction: "up",
+      entries,
+      historyIndex: -1,
+      currentPrompt: text("draft"),
+      currentComments: [],
+      savedPrompt: null,
+    })
+
+    expect(up.handled).toBe(true)
+    if (!up.handled) throw new Error("expected handled")
+    expect(up.entry.prompt[0]?.type === "text" ? up.entry.prompt[0].content : "").toBe("with comment")
+    expect(up.entry.comments).toEqual([comment("c1")])
+  })
+
+  test("normalizePromptHistoryEntry supports legacy prompt arrays", () => {
+    const entry = normalizePromptHistoryEntry(text("legacy"))
+    expect(entry.prompt[0]?.type === "text" ? entry.prompt[0].content : "").toBe("legacy")
+    expect(entry.comments).toEqual([])
+  })
+
+  test("helpers clone prompt and count text content length", () => {
+    const original: Prompt = [
+      { type: "text", content: "one", start: 0, end: 3 },
+      {
+        type: "file",
+        path: "src/a.ts",
+        content: "@src/a.ts",
+        start: 3,
+        end: 12,
+        selection: { startLine: 1, startChar: 1, endLine: 2, endChar: 1 },
+      },
+      { type: "image", id: "1", filename: "img.png", mime: "image/png", dataUrl: "data:image/png;base64,abc" },
+    ]
+    const copy = clonePromptParts(original)
+    expect(copy).not.toBe(original)
+    expect(promptLength(copy)).toBe(12)
+    if (copy[1]?.type !== "file") throw new Error("expected file")
+    copy[1].selection!.startLine = 9
+    if (original[1]?.type !== "file") throw new Error("expected file")
+    expect(original[1].selection?.startLine).toBe(1)
+  })
+
+  test("canNavigateHistoryAtCursor only allows prompt boundaries", () => {
+    const value = "a\nb\nc"
+
+    expect(canNavigateHistoryAtCursor("up", value, 0)).toBe(false)
+    expect(canNavigateHistoryAtCursor("down", value, 0)).toBe(false)
+
+    expect(canNavigateHistoryAtCursor("up", value, 2)).toBe(false)
+    expect(canNavigateHistoryAtCursor("down", value, 2)).toBe(false)
+
+    expect(canNavigateHistoryAtCursor("up", value, 5)).toBe(false)
+    expect(canNavigateHistoryAtCursor("down", value, 5)).toBe(true)
+
+    expect(canNavigateHistoryAtCursor("up", "abc", 0)).toBe(false)
+    expect(canNavigateHistoryAtCursor("down", "abc", 3)).toBe(true)
+    expect(canNavigateHistoryAtCursor("up", "abc", 1)).toBe(false)
+    expect(canNavigateHistoryAtCursor("down", "abc", 1)).toBe(false)
+
+    expect(canNavigateHistoryAtCursor("up", "", 0)).toBe(true)
+    expect(canNavigateHistoryAtCursor("down", "", 0)).toBe(true)
+
+    expect(canNavigateHistoryAtCursor("up", "abc", 0, true)).toBe(true)
+    expect(canNavigateHistoryAtCursor("up", "abc", 3, true)).toBe(true)
+    expect(canNavigateHistoryAtCursor("down", "abc", 0, true)).toBe(true)
+    expect(canNavigateHistoryAtCursor("down", "abc", 3, true)).toBe(true)
+    expect(canNavigateHistoryAtCursor("up", "abc", 1, true)).toBe(false)
+    expect(canNavigateHistoryAtCursor("down", "abc", 1, true)).toBe(false)
+  })
+})

packages/app/src/components/prompt-input/history.ts

@@ -0,0 +1,256 @@
+import type { Prompt } from "@/context/prompt"
+import type { SelectedLineRange } from "@/context/file"
+
+const DEFAULT_PROMPT: Prompt = [{ type: "text", content: "", start: 0, end: 0 }]
+
+export const MAX_HISTORY = 100
+
+export type PromptHistoryComment = {
+  id: string
+  path: string
+  selection: SelectedLineRange
+  comment: string
+  time: number
+  origin?: "review" | "file"
+  preview?: string
+}
+
+export type PromptHistoryEntry = {
+  prompt: Prompt
+  comments: PromptHistoryComment[]
+}
+
+export type PromptHistoryStoredEntry = Prompt | PromptHistoryEntry
+
+export function canNavigateHistoryAtCursor(direction: "up" | "down", text: string, cursor: number, inHistory = false) {
+  const position = Math.max(0, Math.min(cursor, text.length))
+  const atStart = position === 0
+  const atEnd = position === text.length
+  if (inHistory) return atStart || atEnd
+  if (direction === "up") return position === 0 && text.length === 0
+  return position === text.length
+}
+
+export function clonePromptParts(prompt: Prompt): Prompt {
+  return prompt.map((part) => {
+    if (part.type === "text") return { ...part }
+    if (part.type === "image") return { ...part }
+    if (part.type === "agent") return { ...part }
+    return {
+      ...part,
+      selection: part.selection ? { ...part.selection } : undefined,
+    }
+  })
+}
+
+function cloneSelection(selection: SelectedLineRange): SelectedLineRange {
+  return {
+    start: selection.start,
+    end: selection.end,
+    ...(selection.side ? { side: selection.side } : {}),
+    ...(selection.endSide ? { endSide: selection.endSide } : {}),
+  }
+}
+
+export function clonePromptHistoryComments(comments: PromptHistoryComment[]) {
+  return comments.map((comment) => ({
+    ...comment,
+    selection: cloneSelection(comment.selection),
+  }))
+}
+
+export function normalizePromptHistoryEntry(entry: PromptHistoryStoredEntry): PromptHistoryEntry {
+  if (Array.isArray(entry)) {
+    return {
+      prompt: clonePromptParts(entry),
+      comments: [],
+    }
+  }
+  return {
+    prompt: clonePromptParts(entry.prompt),
+    comments: clonePromptHistoryComments(entry.comments),
+  }
+}
+
+export function promptLength(prompt: Prompt) {
+  return prompt.reduce((len, part) => len + ("content" in part ? part.content.length : 0), 0)
+}
+
+export function prependHistoryEntry(
+  entries: PromptHistoryStoredEntry[],
+  prompt: Prompt,
+  comments: PromptHistoryComment[] = [],
+  max = MAX_HISTORY,
+) {
+  const text = prompt
+    .map((part) => ("content" in part ? part.content : ""))
+    .join("")
+    .trim()
+  const hasImages = prompt.some((part) => part.type === "image")
+  const hasComments = comments.some((comment) => !!comment.comment.trim())
+  if (!text && !hasImages && !hasComments) return entries
+
+  const entry = {
+    prompt: clonePromptParts(prompt),
+    comments: clonePromptHistoryComments(comments),
+  } satisfies PromptHistoryEntry
+  const last = entries[0]
+  if (last && isPromptEqual(last, entry)) return entries
+  return [entry, ...entries].slice(0, max)
+}
+
+function isCommentEqual(commentA: PromptHistoryComment, commentB: PromptHistoryComment) {
+  return (
+    commentA.path === commentB.path &&
+    commentA.comment === commentB.comment &&
+    commentA.origin === commentB.origin &&
+    commentA.preview === commentB.preview &&
+    commentA.selection.start === commentB.selection.start &&
+    commentA.selection.end === commentB.selection.end &&
+    commentA.selection.side === commentB.selection.side &&
+    commentA.selection.endSide === commentB.selection.endSide
+  )
+}
+
+function isPromptEqual(promptA: PromptHistoryStoredEntry, promptB: PromptHistoryStoredEntry) {
+  const entryA = normalizePromptHistoryEntry(promptA)
+  const entryB = normalizePromptHistoryEntry(promptB)
+  if (entryA.prompt.length !== entryB.prompt.length) return false
+  for (let i = 0; i < entryA.prompt.length; i++) {
+    const partA = entryA.prompt[i]
+    const partB = entryB.prompt[i]
+    if (partA.type !== partB.type) return false
+    if (partA.type === "text" && partA.content !== (partB.type === "text" ? partB.content : "")) return false
+    if (partA.type === "file") {
+      if (partA.path !== (partB.type === "file" ? partB.path : "")) return false
+      const a = partA.selection
+      const b = partB.type === "file" ? partB.selection : undefined
+      const sameSelection =
+        (!a && !b) ||
+        (!!a &&
+          !!b &&
+          a.startLine === b.startLine &&
+          a.startChar === b.startChar &&
+          a.endLine === b.endLine &&
+          a.endChar === b.endChar)
+      if (!sameSelection) return false
+    }
+    if (partA.type === "agent" && partA.name !== (partB.type === "agent" ? partB.name : "")) return false
+    if (partA.type === "image" && partA.id !== (partB.type === "image" ? partB.id : "")) return false
+  }
+  if (entryA.comments.length !== entryB.comments.length) return false
+  for (let i = 0; i < entryA.comments.length; i++) {
+    const commentA = entryA.comments[i]
+    const commentB = entryB.comments[i]
+    if (!commentA || !commentB || !isCommentEqual(commentA, commentB)) return false
+  }
+  return true
+}
+
+type HistoryNavInput = {
+  direction: "up" | "down"
+  entries: PromptHistoryStoredEntry[]
+  historyIndex: number
+  currentPrompt: Prompt
+  currentComments: PromptHistoryComment[]
+  savedPrompt: PromptHistoryEntry | null
+}
+
+type HistoryNavResult =
+  | {
+      handled: false
+      historyIndex: number
+      savedPrompt: PromptHistoryEntry | null
+    }
+  | {
+      handled: true
+      historyIndex: number
+      savedPrompt: PromptHistoryEntry | null
+      entry: PromptHistoryEntry
+      cursor: "start" | "end"
+    }
+
+export function navigatePromptHistory(input: HistoryNavInput): HistoryNavResult {
+  if (input.direction === "up") {
+    if (input.entries.length === 0) {
+      return {
+        handled: false,
+        historyIndex: input.historyIndex,
+        savedPrompt: input.savedPrompt,
+      }
+    }
+
+    if (input.historyIndex === -1) {
+      const entry = normalizePromptHistoryEntry(input.entries[0])
+      return {
+        handled: true,
+        historyIndex: 0,
+        savedPrompt: {
+          prompt: clonePromptParts(input.currentPrompt),
+          comments: clonePromptHistoryComments(input.currentComments),
+        },
+        entry,
+        cursor: "start",
+      }
+    }
+
+    if (input.historyIndex < input.entries.length - 1) {
+      const next = input.historyIndex + 1
+      const entry = normalizePromptHistoryEntry(input.entries[next])
+      return {
+        handled: true,
+        historyIndex: next,
+        savedPrompt: input.savedPrompt,
+        entry,
+        cursor: "start",
+      }
+    }
+
+    return {
+      handled: false,
+      historyIndex: input.historyIndex,
+      savedPrompt: input.savedPrompt,
+    }
+  }
+
+  if (input.historyIndex > 0) {
+    const next = input.historyIndex - 1
+    const entry = normalizePromptHistoryEntry(input.entries[next])
+    return {
+      handled: true,
+      historyIndex: next,
+      savedPrompt: input.savedPrompt,
+      entry,
+      cursor: "end",
+    }
+  }
+
+  if (input.historyIndex === 0) {
+    if (input.savedPrompt) {
+      return {
+        handled: true,
+        historyIndex: -1,
+        savedPrompt: null,
+        entry: input.savedPrompt,
+        cursor: "end",
+      }
+    }
+
+    return {
+      handled: true,
+      historyIndex: -1,
+      savedPrompt: null,
+      entry: {
+        prompt: DEFAULT_PROMPT,
+        comments: [],
+      },
+      cursor: "end",
+    }
+  }
+
+  return {
+    handled: false,
+    historyIndex: input.historyIndex,
+    savedPrompt: input.savedPrompt,
+  }
+}

packages/app/src/components/prompt-input/image-attachments.tsx

@@ -0,0 +1,61 @@
+import { Component, For, Show } from "solid-js"
+import { Icon } from "@opencode-ai/ui/icon"
+import { Tooltip } from "@opencode-ai/ui/tooltip"
+import type { ImageAttachmentPart } from "@/context/prompt"
+
+type PromptImageAttachmentsProps = {
+  attachments: ImageAttachmentPart[]
+  onOpen: (attachment: ImageAttachmentPart) => void
+  onRemove: (id: string) => void
+  removeLabel: string
+}
+
+const fallbackClass = "size-16 rounded-md bg-surface-base flex items-center justify-center border border-border-base"
+const imageClass =
+  "size-16 rounded-md object-cover border border-border-base hover:border-border-strong-base transition-colors"
+const removeClass =
+  "absolute -top-1.5 -right-1.5 size-5 rounded-full bg-surface-raised-stronger-non-alpha border border-border-base flex items-center justify-center opacity-0 group-hover:opacity-100 transition-opacity hover:bg-surface-raised-base-hover"
+const nameClass = "absolute bottom-0 left-0 right-0 px-1 py-0.5 bg-black/50 rounded-b-md"
+
+export const PromptImageAttachments: Component<PromptImageAttachmentsProps> = (props) => {
+  return (
+    <Show when={props.attachments.length > 0}>
+      <div class="flex flex-wrap gap-2 px-3 pt-3">
+        <For each={props.attachments}>
+          {(attachment) => (
+            <Tooltip value={attachment.filename} placement="top" contentClass="break-all">
+              <div class="relative group">
+                <Show
+                  when={attachment.mime.startsWith("image/")}
+                  fallback={
+                    <div class={fallbackClass}>
+                      <Icon name="folder" class="size-6 text-text-weak" />
+                    </div>
+                  }
+                >
+                  <img
+                    src={attachment.dataUrl}
+                    alt={attachment.filename}
+                    class={imageClass}
+                    onClick={() => props.onOpen(attachment)}
+                  />
+                </Show>
+                <button
+                  type="button"
+                  onClick={() => props.onRemove(attachment.id)}
+                  class={removeClass}
+                  aria-label={props.removeLabel}
+                >
+                  <Icon name="close" class="size-3 text-text-weak" />
+                </button>
+                <div class={nameClass}>
+                  <span class="text-10-regular text-white truncate block">{attachment.filename}</span>
+                </div>
+              </div>
+            </Tooltip>
+          )}
+        </For>
+      </div>
+    </Show>
+  )
+}

packages/app/src/components/prompt-input/paste.ts

@@ -0,0 +1,24 @@
+const LARGE_PASTE_CHARS = 8000
+const LARGE_PASTE_BREAKS = 120
+
+function largePaste(text: string) {
+  if (text.length >= LARGE_PASTE_CHARS) return true
+  let breaks = 0
+  for (const char of text) {
+    if (char !== "\n") continue
+    breaks += 1
+    if (breaks >= LARGE_PASTE_BREAKS) return true
+  }
+  return false
+}
+
+export function normalizePaste(text: string) {
+  if (!text.includes("\r")) return text
+  return text.replace(/\r\n?/g, "\n")
+}
+
+export function pasteMode(text: string) {
+  if (largePaste(text)) return "manual"
+  if (text.includes("\n") || text.includes("\r")) return "manual"
+  return "native"
+}

packages/app/src/components/prompt-input/placeholder.test.ts

@@ -0,0 +1,48 @@
+import { describe, expect, test } from "bun:test"
+import { promptPlaceholder } from "./placeholder"
+
+describe("promptPlaceholder", () => {
+  const t = (key: string, params?: Record<string, string>) => `${key}${params?.example ? `:${params.example}` : ""}`
+
+  test("returns shell placeholder in shell mode", () => {
+    const value = promptPlaceholder({
+      mode: "shell",
+      commentCount: 0,
+      example: "example",
+      suggest: true,
+      t,
+    })
+    expect(value).toBe("prompt.placeholder.shell:example")
+  })
+
+  test("returns summarize placeholders for comment context", () => {
+    expect(promptPlaceholder({ mode: "normal", commentCount: 1, example: "example", suggest: true, t })).toBe(
+      "prompt.placeholder.summarizeComment",
+    )
+    expect(promptPlaceholder({ mode: "normal", commentCount: 2, example: "example", suggest: true, t })).toBe(
+      "prompt.placeholder.summarizeComments",
+    )
+  })
+
+  test("returns default placeholder with example when suggestions enabled", () => {
+    const value = promptPlaceholder({
+      mode: "normal",
+      commentCount: 0,
+      example: "translated-example",
+      suggest: true,
+      t,
+    })
+    expect(value).toBe("prompt.placeholder.normal:translated-example")
+  })
+
+  test("returns simple placeholder when suggestions disabled", () => {
+    const value = promptPlaceholder({
+      mode: "normal",
+      commentCount: 0,
+      example: "translated-example",
+      suggest: false,
+      t,
+    })
+    expect(value).toBe("prompt.placeholder.simple")
+  })
+})

packages/app/src/components/prompt-input/placeholder.ts

@@ -0,0 +1,15 @@
+type PromptPlaceholderInput = {
+  mode: "normal" | "shell"
+  commentCount: number
+  example: string
+  suggest: boolean
+  t: (key: string, params?: Record<string, string>) => string
+}
+
+export function promptPlaceholder(input: PromptPlaceholderInput) {
+  if (input.mode === "shell") return input.t("prompt.placeholder.shell", { example: input.example })
+  if (input.commentCount > 1) return input.t("prompt.placeholder.summarizeComments")
+  if (input.commentCount === 1) return input.t("prompt.placeholder.summarizeComment")
+  if (!input.suggest) return input.t("prompt.placeholder.simple")
+  return input.t("prompt.placeholder.normal", { example: input.example })
+}

packages/app/src/components/prompt-input/slash-popover.tsx

@@ -0,0 +1,141 @@
+import { Component, For, Match, Show, Switch } from "solid-js"
+import { FileIcon } from "@opencode-ai/ui/file-icon"
+import { Icon } from "@opencode-ai/ui/icon"
+import { getDirectory, getFilename } from "@opencode-ai/core/util/path"
+
+export type AtOption =
+  | { type: "agent"; name: string; display: string }
+  | { type: "file"; path: string; display: string; recent?: boolean }
+
+export interface SlashCommand {
+  id: string
+  trigger: string
+  title: string
+  description?: string
+  keybind?: string
+  type: "builtin" | "custom"
+  source?: "command" | "mcp" | "skill"
+}
+
+type PromptPopoverProps = {
+  popover: "at" | "slash" | null
+  setSlashPopoverRef: (el: HTMLDivElement) => void
+  atFlat: AtOption[]
+  atActive?: string
+  atKey: (item: AtOption) => string
+  setAtActive: (id: string) => void
+  onAtSelect: (item: AtOption) => void
+  slashFlat: SlashCommand[]
+  slashActive?: string
+  setSlashActive: (id: string) => void
+  onSlashSelect: (item: SlashCommand) => void
+  commandKeybind: (id: string) => string | undefined
+  t: (key: string) => string
+}
+
+export const PromptPopover: Component<PromptPopoverProps> = (props) => {
+  return (
+    <Show when={props.popover}>
+      <div
+        ref={(el) => {
+          if (props.popover === "slash") props.setSlashPopoverRef(el)
+        }}
+        class="absolute inset-x-0 -top-2 -translate-y-full origin-bottom-left max-h-80 min-h-10
+                 overflow-auto no-scrollbar flex flex-col p-2 rounded-[12px]
+                 bg-surface-raised-stronger-non-alpha shadow-[var(--shadow-lg-border-base)]"
+        onMouseDown={(e) => e.preventDefault()}
+      >
+        <Switch>
+          <Match when={props.popover === "at"}>
+            <Show
+              when={props.atFlat.length > 0}
+              fallback={<div class="text-text-weak px-2 py-1">{props.t("prompt.popover.emptyResults")}</div>}
+            >
+              <For each={props.atFlat.slice(0, 10)}>
+                {(item) => {
+                  const key = props.atKey(item)
+
+                  if (item.type === "agent") {
+                    return (
+                      <button
+                        class="w-full flex items-center gap-x-2 rounded-md px-2 py-0.5"
+                        classList={{ "bg-surface-raised-base-hover": props.atActive === key }}
+                        onClick={() => props.onAtSelect(item)}
+                        onMouseEnter={() => props.setAtActive(key)}
+                      >
+                        <Icon name="brain" size="small" class="text-icon-info-active shrink-0" />
+                        <span class="text-14-regular text-text-strong whitespace-nowrap">@{item.name}</span>
+                      </button>
+                    )
+                  }
+
+                  const isDirectory = item.path.endsWith("/")
+                  const directory = isDirectory ? item.path : getDirectory(item.path)
+                  const filename = isDirectory ? "" : getFilename(item.path)
+
+                  return (
+                    <button
+                      class="w-full flex items-center gap-x-2 rounded-md px-2 py-0.5"
+                      classList={{ "bg-surface-raised-base-hover": props.atActive === key }}
+                      onClick={() => props.onAtSelect(item)}
+                      onMouseEnter={() => props.setAtActive(key)}
+                    >
+                      <FileIcon node={{ path: item.path, type: "file" }} class="shrink-0 size-4" />
+                      <div class="flex items-center text-14-regular min-w-0">
+                        <span class="text-text-weak whitespace-nowrap truncate min-w-0">{directory}</span>
+                        <Show when={!isDirectory}>
+                          <span class="text-text-strong whitespace-nowrap">{filename}</span>
+                        </Show>
+                      </div>
+                    </button>
+                  )
+                }}
+              </For>
+            </Show>
+          </Match>
+          <Match when={props.popover === "slash"}>
+            <Show
+              when={props.slashFlat.length > 0}
+              fallback={<div class="text-text-weak px-2 py-1">{props.t("prompt.popover.emptyCommands")}</div>}
+            >
+              <For each={props.slashFlat}>
+                {(cmd) => (
+                  <button
+                    data-slash-id={cmd.id}
+                    classList={{
+                      "w-full flex items-center justify-between gap-4 rounded-md px-2 py-1": true,
+                      "bg-surface-raised-base-hover": props.slashActive === cmd.id,
+                    }}
+                    onClick={() => props.onSlashSelect(cmd)}
+                    onMouseEnter={() => props.setSlashActive(cmd.id)}
+                  >
+                    <div class="flex items-center gap-2 min-w-0">
+                      <span class="text-14-regular text-text-strong whitespace-nowrap">/{cmd.trigger}</span>
+                      <Show when={cmd.description}>
+                        <span class="text-14-regular text-text-weak truncate">{cmd.description}</span>
+                      </Show>
+                    </div>
+                    <div class="flex items-center gap-2 shrink-0">
+                      <Show when={cmd.type === "custom" && cmd.source !== "command"}>
+                        <span class="text-11-regular text-text-subtle px-1.5 py-0.5 bg-surface-base rounded">
+                          {cmd.source === "skill"
+                            ? props.t("prompt.slash.badge.skill")
+                            : cmd.source === "mcp"
+                              ? props.t("prompt.slash.badge.mcp")
+                              : props.t("prompt.slash.badge.custom")}
+                        </span>
+                      </Show>
+                      <Show when={props.commandKeybind(cmd.id)}>
+                        <span class="text-12-regular text-text-subtle">{props.commandKeybind(cmd.id)}</span>
+                      </Show>
+                    </div>
+                  </button>
+                )}
+              </For>
+            </Show>
+          </Match>
+        </Switch>
+      </div>
+    </Show>
+  )
+}

packages/app/src/components/prompt-input/submit.test.ts

@@ -0,0 +1,358 @@
+import { beforeAll, beforeEach, describe, expect, mock, test } from "bun:test"
+import type { Prompt } from "@/context/prompt"
+
+let createPromptSubmit: typeof import("./submit").createPromptSubmit
+
+const createdClients: string[] = []
+const createdSessions: string[] = []
+const enabledAutoAccept: Array<{ sessionID: string; directory: string }> = []
+const optimistic: Array<{
+  directory?: string
+  sessionID?: string
+  message: {
+    agent: string
+    model: { providerID: string; modelID: string }
+    variant?: string
+  }
+}> = []
+const optimisticSeeded: boolean[] = []
+const storedSessions: Record<string, Array<{ id: string; title?: string }>> = {}
+const promoted: Array<{ directory: string; sessionID: string }> = []
+const sentShell: string[] = []
+const syncedDirectories: string[] = []
+
+let params: { id?: string } = {}
+let selected = "/repo/worktree-a"
+let variant: string | undefined
+
+const promptValue: Prompt = [{ type: "text", content: "ls", start: 0, end: 2 }]
+
+const clientFor = (directory: string) => {
+  createdClients.push(directory)
+  return {
+    session: {
+      create: async () => {
+        createdSessions.push(directory)
+        return {
+          data: {
+            id: `session-${createdSessions.length}`,
+            title: `New session ${createdSessions.length}`,
+          },
+        }
+      },
+      shell: async () => {
+        sentShell.push(directory)
+        return { data: undefined }
+      },
+      prompt: async () => ({ data: undefined }),
+      promptAsync: async () => ({ data: undefined }),
+      command: async () => ({ data: undefined }),
+      abort: async () => ({ data: undefined }),
+    },
+    worktree: {
+      create: async () => ({ data: { directory: `${directory}/new` } }),
+    },
+  }
+}
+
+beforeAll(async () => {
+  const rootClient = clientFor("/repo/main")
+
+  mock.module("@solidjs/router", () => ({
+    useNavigate: () => () => undefined,
+    useParams: () => params,
+    useLocation: () => ({}),
+    useSearchParams: () => [{}, () => undefined],
+  }))
+
+  mock.module("@opencode-ai/sdk/v2/client", () => ({
+    createOpencodeClient: (input: { directory: string }) => {
+      createdClients.push(input.directory)
+      return clientFor(input.directory)
+    },
+  }))
+
+  mock.module("@opencode-ai/ui/toast", () => ({
+    showToast: () => 0,
+  }))
+
+  mock.module("@opencode-ai/core/util/encode", () => ({
+    base64Encode: (value: string) => value,
+  }))
+
+  mock.module("@/context/local", () => ({
+    useLocal: () => ({
+      model: {
+        current: () => ({ id: "model", provider: { id: "provider" } }),
+        variant: { current: () => variant },
+      },
+      agent: {
+        current: () => ({ name: "agent" }),
+      },
+      session: {
+        promote(directory: string, sessionID: string) {
+          promoted.push({ directory, sessionID })
+        },
+      },
+    }),
+  }))
+
+  mock.module("@/context/permission", () => ({
+    usePermission: () => ({
+      enableAutoAccept(sessionID: string, directory: string) {
+        enabledAutoAccept.push({ sessionID, directory })
+      },
+    }),
+  }))
+
+  mock.module("@/context/server", () => ({
+    useServer: () => ({ key: "server-key" }),
+  }))
+
+  mock.module("@/context/tabs", () => ({
+    useTabs: () => ({
+      promoteDraft: () => undefined,
+    }),
+  }))
+
+  mock.module("@/context/prompt", () => ({
+    usePrompt: () => ({
+      current: () => promptValue,
+      reset: () => undefined,
+      set: () => undefined,
+      context: {
+        add: () => undefined,
+        remove: () => undefined,
+        items: () => [],
+      },
+    }),
+  }))
+
+  mock.module("@/context/layout", () => ({
+    useLayout: () => ({
+      handoff: {
+        setTabs: () => undefined,
+      },
+    }),
+  }))
+
+  mock.module("@/context/sdk", () => ({
+    useSDK: () => {
+      const sdk = {
+        scope: "local",
+        directory: "/repo/main",
+        client: rootClient,
+        url: "http://localhost:4096",
+        createClient(opts: any) {
+          return clientFor(opts.directory)
+        },
+      }
+      return sdk
+    },
+  }))
+
+  mock.module("@/context/sync", () => ({
+    useSync: () => ({
+      data: { command: [] },
+      session: {
+        optimistic: {
+          add: (value: {
+            directory?: string
+            sessionID?: string
+            message: { agent: string; model: { providerID: string; modelID: string; variant?: string } }
+          }) => {
+            optimistic.push(value)
+            optimisticSeeded.push(
+              !!value.directory &&
+                !!value.sessionID &&
+                !!storedSessions[value.directory]?.find((item) => item.id === value.sessionID)?.title,
+            )
+          },
+          remove: () => undefined,
+        },
+      },
+      set: () => undefined,
+    }),
+  }))
+
+  mock.module("@/context/server-sync", () => ({
+    useServerSync: () => ({
+      child: (directory: string) => {
+        syncedDirectories.push(directory)
+        storedSessions[directory] ??= []
+        return [
+          { session: storedSessions[directory] },
+          (...args: unknown[]) => {
+            if (args[0] !== "session") return
+            const next = args[1]
+            if (typeof next === "function") {
+              storedSessions[directory] = next(storedSessions[directory]) as Array<{ id: string; title?: string }>
+              return
+            }
+            if (Array.isArray(next)) {
+              storedSessions[directory] = next as Array<{ id: string; title?: string }>
+            }
+          },
+        ]
+      },
+    }),
+  }))
+
+  mock.module("@/context/platform", () => ({
+    usePlatform: () => ({
+      fetch: fetch,
+    }),
+  }))
+
+  mock.module("@/context/language", () => ({
+    useLanguage: () => ({
+      t: (key: string) => key,
+    }),
+  }))
+
+  const mod = await import("./submit")
+  createPromptSubmit = mod.createPromptSubmit
+})
+
+beforeEach(() => {
+  createdClients.length = 0
+  createdSessions.length = 0
+  enabledAutoAccept.length = 0
+  optimistic.length = 0
+  optimisticSeeded.length = 0
+  promoted.length = 0
+  params = {}
+  sentShell.length = 0
+  syncedDirectories.length = 0
+  selected = "/repo/worktree-a"
+  variant = undefined
+  for (const key of Object.keys(storedSessions)) delete storedSessions[key]
+})
+
+describe("prompt submit worktree selection", () => {
+  test("reads the latest worktree accessor value per submit", async () => {
+    const submit = createPromptSubmit({
+      info: () => undefined,
+      imageAttachments: () => [],
+      commentCount: () => 0,
+      autoAccept: () => false,
+      mode: () => "shell",
+      working: () => false,
+      editor: () => undefined,
+      queueScroll: () => undefined,
+      promptLength: (value) => value.reduce((sum, part) => sum + ("content" in part ? part.content.length : 0), 0),
+      addToHistory: () => undefined,
+      resetHistoryNavigation: () => undefined,
+      setMode: () => undefined,
+      setPopover: () => undefined,
+      newSessionWorktree: () => selected,
+      onNewSessionWorktreeReset: () => undefined,
+      onSubmit: () => undefined,
+    })
+
+    const event = { preventDefault: () => undefined } as unknown as Event
+
+    await submit.handleSubmit(event)
+    selected = "/repo/worktree-b"
+    await submit.handleSubmit(event)
+
+    expect(createdClients).toEqual(["/repo/worktree-a", "/repo/worktree-b"])
+    expect(createdSessions).toEqual(["/repo/worktree-a", "/repo/worktree-b"])
+    expect(sentShell).toEqual(["/repo/worktree-a", "/repo/worktree-b"])
+    expect(syncedDirectories).toEqual(["/repo/worktree-a", "/repo/worktree-a", "/repo/worktree-b", "/repo/worktree-b"])
+    expect(promoted).toEqual([
+      { directory: "/repo/worktree-a", sessionID: "session-1" },
+      { directory: "/repo/worktree-b", sessionID: "session-2" },
+    ])
+    expect(syncedDirectories).toEqual(["/repo/worktree-a", "/repo/worktree-a", "/repo/worktree-b", "/repo/worktree-b"])
+  })
+
+  test("applies auto-accept to newly created sessions", async () => {
+    const submit = createPromptSubmit({
+      info: () => undefined,
+      imageAttachments: () => [],
+      commentCount: () => 0,
+      autoAccept: () => true,
+      mode: () => "shell",
+      working: () => false,
+      editor: () => undefined,
+      queueScroll: () => undefined,
+      promptLength: (value) => value.reduce((sum, part) => sum + ("content" in part ? part.content.length : 0), 0),
+      addToHistory: () => undefined,
+      resetHistoryNavigation: () => undefined,
+      setMode: () => undefined,
+      setPopover: () => undefined,
+      newSessionWorktree: () => selected,
+      onNewSessionWorktreeReset: () => undefined,
+      onSubmit: () => undefined,
+    })
+
+    const event = { preventDefault: () => undefined } as unknown as Event
+
+    await submit.handleSubmit(event)
+
+    expect(enabledAutoAccept).toEqual([{ sessionID: "session-1", directory: "/repo/worktree-a" }])
+  })
+
+  test("includes the selected variant on optimistic prompts", async () => {
+    params = { id: "session-1" }
+    variant = "high"
+
+    const submit = createPromptSubmit({
+      info: () => ({ id: "session-1" }),
+      imageAttachments: () => [],
+      commentCount: () => 0,
+      autoAccept: () => false,
+      mode: () => "normal",
+      working: () => false,
+      editor: () => undefined,
+      queueScroll: () => undefined,
+      promptLength: (value) => value.reduce((sum, part) => sum + ("content" in part ? part.content.length : 0), 0),
+      addToHistory: () => undefined,
+      resetHistoryNavigation: () => undefined,
+      setMode: () => undefined,
+      setPopover: () => undefined,
+      onSubmit: () => undefined,
+    })
+
+    const event = { preventDefault: () => undefined } as unknown as Event
+
+    await submit.handleSubmit(event)
+
+    expect(optimistic).toHaveLength(1)
+    expect(optimistic[0]).toMatchObject({
+      message: {
+        agent: "agent",
+        model: { providerID: "provider", modelID: "model", variant: "high" },
+      },
+    })
+  })
+
+  test("seeds new sessions before optimistic prompts are added", async () => {
+    const submit = createPromptSubmit({
+      info: () => undefined,
+      imageAttachments: () => [],
+      commentCount: () => 0,
+      autoAccept: () => false,
+      mode: () => "normal",
+      working: () => false,
+      editor: () => undefined,
+      queueScroll: () => undefined,
+      promptLength: (value) => value.reduce((sum, part) => sum + ("content" in part ? part.content.length : 0), 0),
+      addToHistory: () => undefined,
+      resetHistoryNavigation: () => undefined,
+      setMode: () => undefined,
+      setPopover: () => undefined,
+      newSessionWorktree: () => selected,
+      onNewSessionWorktreeReset: () => undefined,
+      onSubmit: () => undefined,
+    })
+
+    const event = { preventDefault: () => undefined } as unknown as Event
+
+    await submit.handleSubmit(event)
+
+    expect(storedSessions["/repo/worktree-a"]).toEqual([{ id: "session-1", title: "New session 1" }])
+    expect(optimisticSeeded).toEqual([true])
+  })
+})

packages/app/src/components/prompt-input/submit.ts

@@ -0,0 +1,601 @@
+import type { Message, Session } from "@opencode-ai/sdk/v2/client"
+import { showToast } from "@/utils/toast"
+import { base64Encode } from "@opencode-ai/core/util/encode"
+import { Binary } from "@opencode-ai/core/util/binary"
+import { useNavigate, useParams, useSearchParams } from "@solidjs/router"
+import { batch, type Accessor } from "solid-js"
+import type { FileSelection } from "@/context/file"
+import { useServer } from "@/context/server"
+import { useTabs } from "@/context/tabs"
+import { useServerSync } from "@/context/server-sync"
+import { useLanguage } from "@/context/language"
+import { useLayout } from "@/context/layout"
+import { useLocal } from "@/context/local"
+import { usePermission } from "@/context/permission"
+import { type ContextItem, type ImageAttachmentPart, type Prompt, usePrompt } from "@/context/prompt"
+import { useSDK } from "@/context/sdk"
+import { useSync } from "@/context/sync"
+import { Identifier } from "@/utils/id"
+import { Worktree as WorktreeState } from "@/utils/worktree"
+import { buildRequestParts } from "./build-request-parts"
+import { setCursorPosition } from "./editor-dom"
+import { formatServerError } from "@/utils/server-errors"
+import { ScopedKey } from "@/utils/server-scope"
+
+type PendingPrompt = {
+  abort: AbortController
+  cleanup: VoidFunction
+}
+
+const pending = new Map<string, PendingPrompt>()
+
+export type FollowupDraft = {
+  sessionID: string
+  sessionDirectory: string
+  prompt: Prompt
+  context: (ContextItem & { key: string })[]
+  agent: string
+  model: { providerID: string; modelID: string }
+  variant?: string
+}
+
+type FollowupSendInput = {
+  client: ReturnType<typeof useSDK>["client"]
+  serverSync: ReturnType<typeof useServerSync>
+  sync: ReturnType<typeof useSync>
+  draft: FollowupDraft
+  messageID?: string
+  optimisticBusy?: boolean
+  before?: () => Promise<boolean> | boolean
+}
+
+const draftText = (prompt: Prompt) => prompt.map((part) => ("content" in part ? part.content : "")).join("")
+
+const draftImages = (prompt: Prompt) => prompt.filter((part): part is ImageAttachmentPart => part.type === "image")
+
+export async function sendFollowupDraft(input: FollowupSendInput) {
+  const text = draftText(input.draft.prompt)
+  const images = draftImages(input.draft.prompt)
+  const [, setStore] = input.serverSync.child(input.draft.sessionDirectory)
+
+  const setBusy = () => {
+    if (!input.optimisticBusy) return
+    setStore("session_status", input.draft.sessionID, { type: "busy" })
+  }
+
+  const setIdle = () => {
+    if (!input.optimisticBusy) return
+    setStore("session_status", input.draft.sessionID, { type: "idle" })
+  }
+
+  const wait = async () => {
+    const ok = await input.before?.()
+    if (ok === false) return false
+    return true
+  }
+
+  const [head, ...tail] = text.split(" ")
+  const cmd = head?.startsWith("/") ? head.slice(1) : undefined
+  if (cmd && input.sync.data.command.find((item) => item.name === cmd)) {
+    setBusy()
+    try {
+      if (!(await wait())) {
+        setIdle()
+        return false
+      }
+
+      await input.client.session.command({
+        sessionID: input.draft.sessionID,
+        command: cmd,
+        arguments: tail.join(" "),
+        agent: input.draft.agent,
+        model: `${input.draft.model.providerID}/${input.draft.model.modelID}`,
+        variant: input.draft.variant,
+        parts: images.map((attachment) => ({
+          id: Identifier.ascending("part"),
+          type: "file" as const,
+          mime: attachment.mime,
+          url: attachment.dataUrl,
+          filename: attachment.filename,
+        })),
+      })
+      return true
+    } catch (err) {
+      setIdle()
+      throw err
+    }
+  }
+
+  const messageID = input.messageID ?? Identifier.ascending("message")
+  const { requestParts, optimisticParts } = buildRequestParts({
+    prompt: input.draft.prompt,
+    context: input.draft.context,
+    images,
+    text,
+    sessionID: input.draft.sessionID,
+    messageID,
+    sessionDirectory: input.draft.sessionDirectory,
+  })
+
+  const message: Message = {
+    id: messageID,
+    sessionID: input.draft.sessionID,
+    role: "user",
+    time: { created: Date.now() },
+    agent: input.draft.agent,
+    model: { ...input.draft.model, variant: input.draft.variant },
+  }
+
+  const add = () =>
+    input.sync.session.optimistic.add({
+      directory: input.draft.sessionDirectory,
+      sessionID: input.draft.sessionID,
+      message,
+      parts: optimisticParts,
+    })
+
+  const remove = () =>
+    input.sync.session.optimistic.remove({
+      directory: input.draft.sessionDirectory,
+      sessionID: input.draft.sessionID,
+      messageID,
+    })
+
+  batch(() => {
+    setBusy()
+    add()
+  })
+
+  try {
+    if (!(await wait())) {
+      batch(() => {
+        setIdle()
+        remove()
+      })
+      return false
+    }
+
+    await input.client.session.promptAsync({
+      sessionID: input.draft.sessionID,
+      agent: input.draft.agent,
+      model: input.draft.model,
+      messageID,
+      parts: requestParts,
+      variant: input.draft.variant,
+    })
+    return true
+  } catch (err) {
+    batch(() => {
+      setIdle()
+      remove()
+    })
+    throw err
+  }
+}
+
+type PromptSubmitInput = {
+  info: Accessor<{ id: string } | undefined>
+  imageAttachments: Accessor<ImageAttachmentPart[]>
+  commentCount: Accessor<number>
+  autoAccept: Accessor<boolean>
+  mode: Accessor<"normal" | "shell">
+  working: Accessor<boolean>
+  editor: () => HTMLDivElement | undefined
+  queueScroll: () => void
+  promptLength: (prompt: Prompt) => number
+  addToHistory: (prompt: Prompt, mode: "normal" | "shell") => void
+  resetHistoryNavigation: () => void
+  setMode: (mode: "normal" | "shell") => void
+  setPopover: (popover: "at" | "slash" | null) => void
+  newSessionWorktree?: Accessor<string | undefined>
+  onNewSessionWorktreeReset?: () => void
+  shouldQueue?: Accessor<boolean>
+  onQueue?: (draft: FollowupDraft) => void
+  onAbort?: () => void
+  onSubmit?: () => void
+}
+
+type CommentItem = {
+  path: string
+  selection?: FileSelection
+  comment?: string
+  commentID?: string
+  commentOrigin?: "review" | "file"
+  preview?: string
+}
+
+export function createPromptSubmit(input: PromptSubmitInput) {
+  const navigate = useNavigate()
+  const sdk = useSDK()
+  const sync = useSync()
+  const serverSync = useServerSync()
+  const local = useLocal()
+  const permission = usePermission()
+  const prompt = usePrompt()
+  const layout = useLayout()
+  const language = useLanguage()
+  const params = useParams()
+  const [search] = useSearchParams<{ draftId?: string }>()
+  const server = useServer()
+  const tabs = useTabs()
+  const pendingKey = (sessionID: string) => ScopedKey.from(sdk.scope, sessionID)
+
+  const errorMessage = (err: unknown) => {
+    if (err && typeof err === "object" && "data" in err) {
+      const data = (err as { data?: { message?: string } }).data
+      if (data?.message) return data.message
+    }
+    if (err instanceof Error) return err.message
+    return language.t("common.requestFailed")
+  }
+
+  const abort = async () => {
+    const sessionID = params.id
+    if (!sessionID) return Promise.resolve()
+
+    serverSync.todo.set(sessionID, [])
+    const [, setStore] = serverSync.child(sdk.directory)
+    setStore("todo", sessionID, [])
+
+    input.onAbort?.()
+
+    const key = pendingKey(sessionID)
+    const queued = pending.get(key)
+    if (queued) {
+      queued.abort.abort()
+      queued.cleanup()
+      pending.delete(key)
+      return Promise.resolve()
+    }
+    return sdk.client.session
+      .abort({
+        sessionID,
+      })
+      .catch(() => {})
+  }
+
+  const restoreCommentItems = (items: CommentItem[]) => {
+    for (const item of items) {
+      prompt.context.add({
+        type: "file",
+        path: item.path,
+        selection: item.selection,
+        comment: item.comment,
+        commentID: item.commentID,
+        commentOrigin: item.commentOrigin,
+        preview: item.preview,
+      })
+    }
+  }
+
+  const removeCommentItems = (items: { key: string }[]) => {
+    for (const item of items) {
+      prompt.context.remove(item.key)
+    }
+  }
+
+  const clearContext = () => {
+    for (const item of prompt.context.items()) {
+      prompt.context.remove(item.key)
+    }
+  }
+
+  const seed = (dir: string, info: Session) => {
+    const [, setStore] = serverSync.child(dir)
+    setStore("session", (list: Session[]) => {
+      const result = Binary.search(list, info.id, (item) => item.id)
+      const next = [...list]
+      if (result.found) {
+        next[result.index] = info
+        return next
+      }
+      next.splice(result.index, 0, info)
+      return next
+    })
+  }
+
+  const handleSubmit = async (event: Event) => {
+    event.preventDefault()
+
+    const currentPrompt = prompt.current()
+    const text = currentPrompt.map((part) => ("content" in part ? part.content : "")).join("")
+    const images = input.imageAttachments().slice()
+    const mode = input.mode()
+
+    if (text.trim().length === 0 && images.length === 0 && input.commentCount() === 0) {
+      if (input.working()) void abort()
+      return
+    }
+
+    const currentModel = local.model.current()
+    const currentAgent = local.agent.current()
+    const variant = local.model.variant.current()
+    if (!currentModel || !currentAgent) {
+      showToast({
+        title: language.t("prompt.toast.modelAgentRequired.title"),
+        description: language.t("prompt.toast.modelAgentRequired.description"),
+      })
+      return
+    }
+
+    input.addToHistory(currentPrompt, mode)
+    input.resetHistoryNavigation()
+
+    const projectDirectory = sdk.directory
+    const isNewSession = !params.id
+    const shouldAutoAccept = isNewSession && input.autoAccept()
+    const worktreeSelection = input.newSessionWorktree?.() || "main"
+
+    let sessionDirectory = projectDirectory
+    let client = sdk.client
+
+    if (isNewSession) {
+      if (worktreeSelection === "create") {
+        const createdWorktree = await client.worktree
+          .create({ directory: projectDirectory })
+          .then((x) => x.data)
+          .catch((err) => {
+            showToast({
+              title: language.t("prompt.toast.worktreeCreateFailed.title"),
+              description: errorMessage(err),
+            })
+            return undefined
+          })
+
+        if (!createdWorktree?.directory) {
+          showToast({
+            title: language.t("prompt.toast.worktreeCreateFailed.title"),
+            description: language.t("common.requestFailed"),
+          })
+          return
+        }
+        WorktreeState.pending(sdk.scope, createdWorktree.directory)
+        sessionDirectory = createdWorktree.directory
+      }
+
+      if (worktreeSelection !== "main" && worktreeSelection !== "create") {
+        sessionDirectory = worktreeSelection
+      }
+
+      if (sessionDirectory !== projectDirectory) {
+        client = sdk.createClient({
+          directory: sessionDirectory,
+          throwOnError: true,
+        })
+        serverSync.child(sessionDirectory)
+      }
+
+      input.onNewSessionWorktreeReset?.()
+    }
+
+    let session = input.info()
+    if (!session && isNewSession) {
+      const created = await client.session
+        .create()
+        .then((x) => x.data ?? undefined)
+        .catch((err) => {
+          showToast({
+            title: language.t("prompt.toast.sessionCreateFailed.title"),
+            description: errorMessage(err),
+          })
+          return undefined
+        })
+      if (created) {
+        seed(sessionDirectory, created)
+        session = created
+        if (shouldAutoAccept) permission.enableAutoAccept(session.id, sessionDirectory)
+        local.session.promote(sessionDirectory, session.id)
+        layout.handoff.setTabs(base64Encode(sessionDirectory), session.id)
+        const draftID = search.draftId
+        if (draftID)
+          tabs.promoteDraft(draftID, {
+            server: server.key,
+            dirBase64: base64Encode(sessionDirectory),
+            sessionId: session.id,
+          })
+        else navigate(`/${base64Encode(sessionDirectory)}/session/${session.id}`)
+      }
+    }
+    if (!session) {
+      showToast({
+        title: language.t("prompt.toast.promptSendFailed.title"),
+        description: language.t("prompt.toast.promptSendFailed.description"),
+      })
+      return
+    }
+
+    const model = {
+      modelID: currentModel.id,
+      providerID: currentModel.provider.id,
+    }
+    const agent = currentAgent.name
+    const context = prompt.context.items().slice()
+    const draft: FollowupDraft = {
+      sessionID: session.id,
+      sessionDirectory,
+      prompt: currentPrompt,
+      context,
+      agent,
+      model,
+      variant,
+    }
+
+    const clearInput = () => {
+      prompt.reset()
+      input.setMode("normal")
+      input.setPopover(null)
+    }
+
+    const restoreInput = () => {
+      prompt.set(currentPrompt, input.promptLength(currentPrompt))
+      input.setMode(mode)
+      input.setPopover(null)
+      requestAnimationFrame(() => {
+        const editor = input.editor()
+        if (!editor) return
+        editor.focus()
+        setCursorPosition(editor, input.promptLength(currentPrompt))
+        input.queueScroll()
+      })
+    }
+
+    if (!isNewSession && mode === "normal" && input.shouldQueue?.()) {
+      input.onQueue?.(draft)
+      clearContext()
+      clearInput()
+      return
+    }
+
+    input.onSubmit?.()
+
+    if (mode === "shell") {
+      clearInput()
+      client.session
+        .shell({
+          sessionID: session.id,
+          agent,
+          model,
+          command: text,
+        })
+        .catch((err) => {
+          showToast({
+            title: language.t("prompt.toast.shellSendFailed.title"),
+            description: errorMessage(err),
+          })
+          restoreInput()
+        })
+      return
+    }
+
+    if (text.startsWith("/")) {
+      const [cmdName, ...args] = text.split(" ")
+      const commandName = cmdName.slice(1)
+      const customCommand = sync.data.command.find((c) => c.name === commandName)
+      if (customCommand) {
+        clearInput()
+        client.session
+          .command({
+            sessionID: session.id,
+            command: commandName,
+            arguments: args.join(" "),
+            agent,
+            model: `${model.providerID}/${model.modelID}`,
+            variant,
+            parts: images.map((attachment) => ({
+              id: Identifier.ascending("part"),
+              type: "file" as const,
+              mime: attachment.mime,
+              url: attachment.dataUrl,
+              filename: attachment.filename,
+            })),
+          })
+          .catch((err) => {
+            showToast({
+              title: language.t("prompt.toast.commandSendFailed.title"),
+              description: formatServerError(err, language.t, language.t("common.requestFailed")),
+            })
+            restoreInput()
+          })
+        return
+      }
+    }
+
+    const commentItems = context.filter((item) => item.type === "file" && !!item.comment?.trim())
+    const messageID = Identifier.ascending("message")
+
+    const removeOptimisticMessage = () => {
+      sync.session.optimistic.remove({
+        directory: sessionDirectory,
+        sessionID: session.id,
+        messageID,
+      })
+    }
+
+    removeCommentItems(commentItems)
+    clearInput()
+
+    const waitForWorktree = async () => {
+      const worktree = WorktreeState.get(sdk.scope, sessionDirectory)
+      if (!worktree || worktree.status !== "pending") return true
+
+      if (sessionDirectory === projectDirectory) {
+        sync.set("session_status", session.id, { type: "busy" })
+      }
+
+      const controller = new AbortController()
+      const cleanup = () => {
+        if (sessionDirectory === projectDirectory) {
+          sync.set("session_status", session.id, { type: "idle" })
+        }
+        removeOptimisticMessage()
+        restoreCommentItems(commentItems)
+        restoreInput()
+      }
+
+      pending.set(pendingKey(session.id), { abort: controller, cleanup })
+
+      const abortWait = new Promise<Awaited<ReturnType<typeof WorktreeState.wait>>>((resolve) => {
+        if (controller.signal.aborted) {
+          resolve({ status: "failed", message: "aborted" })
+          return
+        }
+        controller.signal.addEventListener(
+          "abort",
+          () => {
+            resolve({ status: "failed", message: "aborted" })
+          },
+          { once: true },
+        )
+      })
+
+      const timeoutMs = 5 * 60 * 1000
+      const timer = { id: undefined as number | undefined }
+      const timeout = new Promise<Awaited<ReturnType<typeof WorktreeState.wait>>>((resolve) => {
+        timer.id = window.setTimeout(() => {
+          resolve({
+            status: "failed",
+            message: language.t("workspace.error.stillPreparing"),
+          })
+        }, timeoutMs)
+      })
+
+      const result = await Promise.race([WorktreeState.wait(sdk.scope, sessionDirectory), abortWait, timeout]).finally(
+        () => {
+          if (timer.id === undefined) return
+          clearTimeout(timer.id)
+        },
+      )
+      pending.delete(pendingKey(session.id))
+      if (controller.signal.aborted) return false
+      if (result.status === "failed") throw new Error(result.message)
+      return true
+    }
+
+    void sendFollowupDraft({
+      client,
+      sync,
+      serverSync,
+      draft,
+      messageID,
+      optimisticBusy: sessionDirectory === projectDirectory,
+      before: waitForWorktree,
+    }).catch((err) => {
+      pending.delete(pendingKey(session.id))
+      if (sessionDirectory === projectDirectory) {
+        sync.set("session_status", session.id, { type: "idle" })
+      }
+      showToast({
+        title: language.t("prompt.toast.promptSendFailed.title"),
+        description: errorMessage(err),
+      })
+      removeOptimisticMessage()
+      restoreCommentItems(commentItems)
+      restoreInput()
+    })
+  }
+
+  return {
+    abort,
+    handleSubmit,
+  }
+}