Tool Policy

Tool policy is configured per agent in lobu.config.ts via defineAgent({ tools }), not in SKILL.md.

Use the tools field for two separate concerns:

• Worker-side tool visibility: allowed, denied, strict
• MCP approval bypass: preApproved

import { defineAgent } from "@lobu/cli/config";

const support = defineAgent({
  id: "support",
  name: "support",
  dir: "./agents/support",
  tools: {
    preApproved: ["/mcp/gmail/tools/list_messages", "/mcp/linear/tools/*"],
    allowed: ["Read", "Grep", "mcp__gmail__*"],
    denied: ["Bash(rm:*)"],
    strict: false,
  },
});

What Each Field Does

• allowed: tools the worker can call
• denied: tools to always block; takes precedence over allowed
• strict: when true, only allowed tools are visible to the worker
• preApproved: MCP tool grant patterns that skip the in-thread approval card

Why This Lives In lobu.config.ts

Tool policy is operator-controlled configuration. Skills can add instructions, MCP servers, network domains, and packages, but they cannot silently widen tool access or pre-approve destructive MCP calls.

That split keeps approval overrides visible in code review and prevents a skill from bypassing the thread-level consent flow.

Skills vs Agent Config

• Use SKILL.md for instructions and capability declarations such as MCP servers, Nix packages, and network requirements.
• Use lobu.config.ts for operator policy such as tool visibility and preApproved MCP grants.

Reference

For the exact schema and field definitions, see the lobu.config.ts reference section for the agent tools field.