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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, openWorld), yet the description adds real behavioral context: cursor-based pagination, a read-scope requirement, and dual auth (Bearer header or key argument). The credential-retention warning is useful but is largely duplicated in the key parameter's schema description.

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 sentences, front-loaded with the core purpose before behavior and credential caveats. Efficient overall, though the trailing security warning partially repeats what the schema already says.

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?

For a 4-param list tool with no output schema, the description covers the essentials an agent needs: what is returned (private community posts), pagination mechanics, scope, and authentication. The only gap is that nothing explains the response shape, though a list tool's output is largely self-evident.

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 description coverage is 75% and the schema already documents key, limit (1-100) and cursor. The description reinforces pagination and the key/auth choice but adds no format detail for community_id, which has no description in either place. Baseline 3 is appropriate when the schema does most of the work.

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 first sentence gives a specific verb (List), resource (private posts/threads), and a scoping condition (community where this account is a member). This distinguishes it well from community_thread_create and community_post_moderate, though it does not explicitly contrast itself with the singular community_thread sibling.

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?

It states the membership precondition and the required read scope, which implies when the call is valid, but it never names an alternative (e.g., community_thread for a single thread) or states when not to use it. Usage is implied rather than guided.

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