Which tools each agent gets

Handing an agent every tool you have makes it worse, not better. The cost lands in the choosing rather than the running, and a tool being available reads to the agent as permission to use it. So the toolset is a design decision, scoped to the role.

Common questions

1. Why does giving an agent more tools make it worse?
   More tools means the agent has to do more selecting work. A small scoped set of four or five it chooses from reliably, where a big shared toolbox of eighteen it does not. The cost is in the selecting, not the running.
2. What happens when a tool does not fit the agent's role?
   The agent wanders out of its lane, because a tool being available reads to it as permission to use it. A synthesis agent handed a web search tool starts searching instead of synthesising.
3. How tightly should I scope a toolset?
   As tight as possible by default. Each agent gets its own role's kit and no more, like an electrician who carries their electrical kit and still calls the carpenter for a doorway.
4. Can an agent have anything outside its role?
   One narrow extra, aligned with something it needs constantly. The electrician carries a drill for the cable holes they make all day. Make the extra do several things and you have rebuilt the big toolbox the scoping was avoiding.
5. How do I decide whether a cross-role need gets its own tool?
   How often and how hard. A common, simple cross-role need gets its own small tool. A rare, complex one gets no tool and routes back to the coordinator instead. The drill for the cable holes, the carpenter for the doorway.
6. Who sets a helper's tools, the helper or the parent?
   The parent controls it. The coordinator holds the full toolset and, when it spawns a helper, deliberately hands down only the slice that helper's role needs, as a restriction on the child.
7. Is it better to constrain the tool or the instruction?
   The tool. If the requirement lives in the instruction there is a chance of it landing too broadly, where a constraint built into the tool means it cannot do the broad thing at all. So fetch-anything becomes load-documents-only, checked.
8. Can I make the model use a tool rather than just answer?
   Yes, and there are three levels. Loosest lets it use a tool or just answer, the middle forces it to reach for some tool of its choosing, and the tightest names the exact one it has to use.
9. Why would I force one exact tool?
   To lock the order rather than to help it choose. Force the extraction step so it runs first, then release the rest, because asking for it first only tends where forcing makes it happen.

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