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

Annotations (readOnlyHint=false, openWorldHint=true, destructiveHint=false) already flag a mutating, outward-facing operation. The description adds real value beyond them: the applicant is not notified with a reason, each call is confirmed by default, and it reaches other people. These are meaningful behavioral disclosures not present in the structured fields.

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-loaded with the action, which is good, but the leading 'Skool:' duplicates the title and the confirmation guidance is split across two sentences ('By default you confirm each call...' and 'Reaches other people: confirm with the user before each call') in a slightly redundant way.

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 two-parameter mutation tool with no output schema, the description covers behavior (no reason given to applicant), safety (confirmation default), auth requirements, and scope. Only the routing to sibling tools is missing, so it is nearly 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?

Schema description coverage is 100% with both parameters documented (group URL name, request_id sourced from list_membership_requests). The description adds no parameter-level detail, so the baseline 3 applies since the schema does the heavy lifting.

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 (Decline) and resource (applicant's request to join), and clarifies scope with 'Declines one pending request.' An agent can distinguish it from listing tools, though it never names the sibling skool_approve_membership_request or skool_list_membership_requests as the counterpart.

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?

Gives operational context (default confirmation, requires user confirmation because it reaches other people, needs a Cotlet API key with app access), but never states when to prefer this over sibling tools like approve_membership_request or when it is inappropriate. Usage is implied rather than spelled out as when/when-not.

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