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

Annotations already establish readOnlyHint and idempotentHint. The description adds behavioral value by specifying that guides are returned as markdown, a `#section` suffix is accepted, endpoints are rendered from the OpenAPI definition, and schemas correspond to response models. No contradiction with annotations.

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?

The description is a single, dense sentence with the core purpose front-loaded and the id variants compactly listed. Every clause earns its place; 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 one required parameter, an output schema, and read-only/idempotent annotations, the description covers the essential call details. The only minor gap is not explicitly routing around get_endpoint/list_endpoints, but the 'one id from search' framing makes the tool's role adequately complete.

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 schema only says the id is 'returned by `search`', while the description defines the exact accepted id grammar: `docs/<slug>`, `op/<operationId>`, and `schema/<name>`. This is essential semantic detail beyond the schema.

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 description states a specific verb ('fetch'), a resource ('docs page, endpoint or model'), and the exact scope: 'Full text for one id from `search`'. It also enumerates the accepted id forms, distinguishing it from the search/list siblings.

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?

'Full text for one id from `search`' clearly implies this tool is the follow-up to a search call, which provides the id. It does not explicitly contrast itself with get_endpoint or list_endpoints, but the single-id context is clear enough for an agent to select it.

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