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

Annotations already indicate readOnlyHint=true, idempotentHint=true, and destructiveHint=false. The description adds value by stating 'Read-only' (consistent with annotations) and disclosing the authorization requirement (must be creator or admin). It doesn't mention other behavioral aspects like pagination or rate limits, but with good annotation coverage, the additional context is sufficient.

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 extremely concise—two sentences—with no unnecessary words. It front-loads the main purpose and includes key usage details without redundancy. Every sentence earns its place.

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 simple tool with one parameter and good annotations, the description is mostly complete: it covers purpose, parameters, authorization, and related actions. It could optionally mention ordering or limit behavior, but the lack of output schema does not hurt here. A 4 is appropriate as it leaves minimal gaps.

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?

With 0% schema description coverage, the description compensates by explaining that community_id is required and that the user must be the creator or admin. It adds meaning beyond the schema's bare minLength/maxLength constraints, giving context on authorization. A 5 might require more detail on the parameter's format or expected values.

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 clearly states the tool lists pending requests to join a community, specifying what information is included (who asked and when). It distinguishes from siblings like approve_join_request and reject_join_request by mentioning them as follow-up actions, and the scope 'community you run' differentiates it from other list tools.

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 provides clear context: requires community_id and creator/admin role. It implicitly says when to use (when you need to see pending join requests) and mentions the approve/reject alternatives. However, it doesn't explicitly compare to other list tools or state when not to use this tool, so it falls short of a 5.

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