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

Annotations already declare readOnlyHint=true and idempotentHint=true, so the safety profile is covered. The description adds genuine behavioral context beyond that: the response includes attribution, origin, and sharing terms, which tells the agent what it gets back. No auth, rate-limit, or error behavior is discussed.

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?

Two sentences, no filler. The content description is front-loaded and the routing instruction follows immediately; every clause earns its place.

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?

An output schema exists, so return shape is already documented, yet the description still summarizes the payload. With a single 100%-documented parameter, annotations covering safety, and explicit id provenance, nothing an agent needs to invoke this correctly is missing.

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?

Schema coverage is 100% and the id field even carries an example (cyborgism, siena), so the baseline is 3. The description adds meaning by specifying the id must originate from list_poems or search_poems, which is provenance guidance the schema does not provide.

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?

States a specific resource (one poem, in full) and enumerates what comes with it — attribution, provenance, sharing terms. This clearly separates it from list_poems and search_poems, which return collections rather than a single complete poem. It never states the retrieval verb explicitly, leaning on the title for that, which keeps it just short of a 5.

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 the id from list_poems or search_poems" explicitly tells the agent the prerequisite and names the two sibling tools that produce valid input. It does not contrast against random_poem or state when NOT to use this tool, so it stops short of full when/when-not guidance.

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