Tools

A "tool" in the agent platform is anything the LLM can call mid-loop. Three flavors are wired today: Matrix tools (projected onto a (target, op) pair on the bus), MCP-bridged tools (for situated workers like Claude Code or Codex), and SDK-private tools (filesystem, shell — not part of this surface).

Pages

• Tool registry — BUILT_IN_TOOL_CONTEXTS, MatrixToolProjection, and how tools enter a session.
• Tool permissions — allowedTargets, allowedOps, approvalRequiredFor, deny, and the security delegate.
• Tool invocation — call dispatch through IToolDelegate.buildTools and system.tools.mcpBridge.tool.invoke.
• Tool traces — how tool.call and tool.result activity frames are emitted.
• Tool testing — what's testable today and what's filed as TODO.

See also

• Tools overview
• Reference: tool schema

Source: projects/matrix-3/packages/agents/src/tools/, projects/matrix-3/packages/agents/src/runtime/AgentEnvironmentSpec.ts.