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

Goes well beyond the annotations (destructiveHint, readOnlyHint, idempotentHint) by disclosing the critical business consequence "NO REFUND either way", that the member is emailed, that they remain a free member, and the authorization requirement (creator or admin only). This is exactly the extra context annotations cannot convey.

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?

Front-loads the core action, then the two modes, then the critical no-refund warning, then side effects and requirements. Every sentence carries distinct information 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?

For a destructive mutation tool with no output schema and 0% schema coverage, the description supplies everything needed to call it correctly: mode semantics, refund behavior, side effects, and permissions. Nothing material 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?

Schema description coverage is 0%, so the description carries the full burden and does so: it defines the semantics of the "when" enum values including which is the default, and confirms community_id and user_id as required. This fully compensates for the empty schema documentation.

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 (Cancel) and resource (a member's paid membership) with clear scope ("in a community you run"). It explicitly distinguishes itself from the sibling remove_community_member, so an agent can route correctly without opening either schema.

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?

Explains both operating modes with their conditions: "period_end" (default) turns renewal off while preserving paid access, and "now" ends access immediately. It also names the alternative tool (remove_community_member) and the condition that selects it, leaving nothing to inference.

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