Track 2 — Builder 构建 · M6 · 40 min · Sandbox by 31 Aug 2026
Dynamic tool registry + scope enforcement (W1/W2)
The model searches a tool registry instead of receiving every tool. Scope enforcement resolves whether a twin may invoke a tool at all.
Prerequisites: M5 · Skills & SKILL.md manifests
After this module you can…
- Explain why the model searches tools instead of receiving all of them.
- Trace an out-of-scope invocation to its refusal.
Key points
- Two meta-tools — tool_search and tool_invoke — keep the prompt small as the catalogue grows.
- Scope is resolved server-side against the twin's assigned skills.
Hands-on exercise: Provoke a refusal
- Ask a Specialist to use a tool from a skill it does not have.
- Read the refusal and find the scope check in the run.
Evidence of success: A refusal citing scope, not a hallucinated success.
Knowledge check
Getting it wrong is fine — the explanation tells you why.
1. Why not hand the model every tool?
2. Where is scope enforced?
Module 6 of 20 · progress is stored on this device.