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

Annotations already cover readOnly/destructive/openWorld, yet the description adds ordering ('newest first'), the exact return shape, the drafts-exclusion rule, and an auth prerequisite ('Needs the user's Cotlet API key with access to this app'). That auth requirement is genuinely new context beyond the annotations.

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 resource and scope, but the first and second sentences both restate 'group' and the filled-slot count ('how many slots are filled' vs 'count of filled and wanted spots'), which is redundant. Roughly a third of the text repeats itself.

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?

With no output schema, the description correctly carries the return-value burden by naming fields and ordering, and it flags pagination keys and auth. Nothing critical is missing for calling the tool, though the pagination/filter interaction is only lightly covered.

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 coverage is 100%, so baseline is 3, but the description adds real meaning: drafts are only returned when status is explicitly 'drafts', a behavior the schema enum alone does not convey. The other two params (limit, cursor) get no added detail, keeping it below 5.

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 and resource ('Sign-ups you created') and scopes it to the authenticated user, which separates it from get_signup or list_participants. It does not explicitly name a sibling it is not, so it stops short of a 5.

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 one useful routing hint ('Use signup_id from each item in the other endpoints') and a filter behavior note, but never states when to choose this over list_participants, list_groups, or get_signup. Usage is implied rather than enumerated.

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