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

Goes well beyond the annotations by explaining the downstream effect of each branch: accepting opens a chat, declining is private, the requester is never notified, and unanswered requests auto-expire after 30 days. That is exactly the kind of consequence detail destructiveHint=true 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?

Four short sentences, front-loaded with the core action, then consequences, then the confirmation instruction. Every sentence adds information an agent would otherwise have to guess.

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, idempotent mutation with no output schema, the description covers both branches, the silent/expiry behavior, and the required user confirmation. The only gap is the join_code edge case for new members, which is left entirely to the schema.

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 only 33%, and the description never explains the action enum or match_id directly, though it implies match_id originates from list_matches. join_code carries a schema description, but the description offers no compensating detail for the undocumented parameters.

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 pair (accept/decline) applied to a specific resource (introduction request), and anchors it to the sibling tool that produces those requests (status pending in list_matches). This clearly separates it from send_intro_request and list_matches.

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 the triggering condition (a request waiting on the user, pending in list_matches) and an explicit interaction guardrail: 'Confirm with the user before declining.' It doesn't spell out when to prefer accepting vs declining, but the decision is the user's by design.

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