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

Annotations already declare mutation (readOnlyHint=false) and non-destructiveness, and the description adds substantial extra context: no notifications are sent ('reaches no one'), the sign-up retains its status so draft slots stay hidden, each new slot ID is returned, and a Cotlet API key with app access is required.

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 front-loaded sentences; the core action and multiplicity rule lead, followed by visibility and auth details. Dense but each sentence carries distinct information, with only mild redundancy in the auth note.

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 mutation tool with no output schema, the description covers what it creates, how many, the return value (slot IDs), the visibility/status behavior, the lack of notifications, and the auth prerequisite. Nothing an agent needs to call it correctly 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?

With 100% schema coverage the baseline is 3, but the description adds real meaning: 'Adds one slot per date-time you pass, all with the same title and quantity,' which explains the multiplicity semantics of the dates array beyond the schema's own wording.

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 ('Add slots (roles or tasks) to a sign-up') plus the scope ('on one or more dates and times'). An agent can immediately distinguish this from signupgenius_update_slot or signupgenius_create_signup.

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 gives behavioral context ('runs without asking first', 'added to a draft stay hidden') that implies when it is safe to call, but it never names an alternative tool or states an explicit when-not-to-use. Usage is implied rather than directed.

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