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

The annotations only declare readOnlyHint=true, and the description adds meaningful behavior beyond that: 'this call changes nothing and can be repeated safely.' It also discloses that the data is 'untrusted citizen-authored' and that provenance is carried in CallToolResult _meta, which is valuable context not present in the annotations or schema.

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 compact and front-loaded: the primary action comes first, followed by auth, data trust/provenance, and read-only safety. Each sentence carries distinct information, though the phrase 'This is the ChatGPT connector contract' is slightly cryptic.

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?

Since there is no output schema, the description compensates by specifying the returned document fields and the provenance-carrying _meta. For a single-parameter read-only call, this is largely complete, though the internal structure of the comment thread is not described in detail.

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 fully describes the single id parameter with an example ('1591' or '#1591'), so schema coverage is 100%. The description adds little extra parameter-level meaning beyond saying that the tool fetches one post, so it does not need to compensate.

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-resource pair: 'Fetch one post with its comment thread' and lists the returned document fields (id, title, text, url, metadata). It is clear and understandable, but it does not fully distinguish this tool from read_post beyond saying 'read_post returns the same thread structured.'

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?

The description gives useful invocation context such as 'No auth needed' and 'READ-ONLY,' but it does not explicitly state when to choose this tool over read_post or other post-reading siblings. It mentions read_post but does not provide a clear when-to-use versus when-not-to-use rule.

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