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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so the safety profile is covered structurally. The description adds genuinely new behavioral detail that the annotations cannot convey: the return shape is limited to category ids and counts. It does not discuss caching or rate limits, but with annotations carrying the safe-read signal that gap is minor.

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 short sentences, each load-bearing: what it returns, why to use it, and what the output contains. The purpose and the find_tools routing are front-loaded with 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 no input params and no output schema, the description fully carries the burden and does so: it names the sibling it feeds, gives examples of the categories, and discloses that only ids and counts are returned. Nothing needed to call it 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?

Zero parameters, so the baseline is 4. The empty schema is consistent with the description, which correctly implies no filtering inputs are required.

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 verb and resource ('Lists the capability categories used by find_tools') and immediately grounds it with concrete examples (web-search, web-scraping, developer-tools) plus the count payload. An agent can distinguish this from the many list_* siblings because the tie to find_tools is explicit.

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?

Gives a clear use condition: call it to pick a capability filter before calling find_tools. That is real routing guidance rather than implied usage. It stops short of an exclusion (e.g., when you already know the category), so not a 5.

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