# ADR-0007: Use ToolRegistry, PermissionEngine, And Capability Manifests

- Status: Accepted
- Date: 2026-05-27

## Context

AirCoding needs a growing tool surface across filesystem, shell, git, build, debug, GUI, network, memory, and future plugins. Tools must be extensible without bypassing safety boundaries.

## Decision

Use ToolRegistry for schema-validated tool execution, PermissionEngine for all side-effect decisions, and CapabilityRegistry for built-in/future tool bundles.

Capabilities declare dependencies and permissions. Doctor/setup detects and installs/fixes dependencies according to permission policy. Capability tools are not privileged above built-ins.

## Consequences

- All tool calls share lifecycle events, artifacts, errors, and evidence behavior.
- Plugin/capability extension is possible without opening a permission bypass.
- Doctor owns dependency installation rather than arbitrary plugin scripts.
- MVP tool names and schemas are frozen in `tool-registry-v1.md`.