Fusion (read)

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnly/idempotent/non-destructive, so the bar is lower; the description still adds real behavior detail beyond them — comp_info returns undo stack and selection, tool_inputs resolves values at a time and paginates keyframes, registry_types searches ~1300 ids with limit/offset. It does not mention pagination defaults, result caps, or whether a live Resolve instance is required.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Purpose is front-loaded in one sentence, followed by a compact bulleted action list with a shared legend for required markers. Every line carries a distinct action; there is no filler.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

With an output schema present, return values need not be explained, and all five enum actions are covered with their parameters. The remaining gap is domain linkage: it never explains what "item" vs "comp" mean or how to obtain an item id before calling comp_info/tool_inputs.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The top-level schema is deliberately generic (additionalProperties: true, "see the description or this server's describe_action tool"), so the description is the only place the real per-action parameters appear — and it lists them for all five actions with a "* = required" legend. This is genuine semantic content the schema does not provide, not repetition.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The opening sentence gives a specific verb and resource ("Read fusion state, no side effects") and states the intended outcome ("find ids and check results"). The five enumerated actions each name a concrete resource (comp structure, compositions, .fuse files, registry ids, tool inputs), so the tool is clearly separable from fusion_write and fusion_delete.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

"use it to find ids and check results" plus "no side effects" tells the agent the situation this tool fits and implicitly contrasts with the write/delete siblings. It never names fusion_write, fusion_delete, or describe_action as the alternative for mutating or for deeper parameter lookup, so the routing is clear but not explicit.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.