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

Annotations only declare readOnly/idempotent/openWorld; the description adds the substantive behavior: returns matching reference pages, returns the page itself on an exact match, enumerations live on member pages, and unmatched names degrade to search results. That is genuine disclosure about output shape and failure mode that annotations cannot supply.

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?

Three dense sentences, front-loaded with the core action, then the return behavior, then the not-found behavior. Every sentence carries distinct information; no restatement of the title or 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?

No output schema exists, so the description carries the return-value burden and does so (reference pages, exact-match page, search results fallback). With only two well-documented parameters and full annotation coverage of safety, 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%, so the baseline is 3; the description still adds meaning by clarifying that 'name' may be partial or misspelt, which the schema does not state. The 'product' parameter's conditional logic (set for technical questions, omit for purchasing/licensing) is carried by the schema itself, not the description.

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 precise verb+resource ('Find a class or member of a WebSupergoo API by name') and grounds it with three concrete examples (Doc.AddImageUrl, AddImageUrl, XImage.SetFile). The tool's identity as an exact-name resolver rather than a general search is clear, which separates it from siblings search and fetch.

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?

Usage context is clear: use it for a class/member name, tolerate partial or misspelt input, and note that enumerations surface on member pages. It never names a sibling tool or says explicitly when to use it over search or contents, but the fallback sentence ('a name that isn't in the API gets search results instead') tells the agent what happens when this tool is the wrong choice.

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