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

Annotations cover the safety profile (readOnlyHint=false, destructiveHint=false), and the description adds real value beyond them: it discloses that it "changes only your own records," is reversible with one more call, so it runs without confirming, and requires a Cotlet API key with app access. That is meaningful behavioral context, not a restatement.

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?

The purpose and the phone/mail scoping are front-loaded, and each following clause (prerequisites, reversibility, auth) carries distinct information. It is dense but not padded; only minor tightening is possible.

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 annotations present and no output schema, the description covers prerequisites, reversibility, confirmation behavior, and auth requirements. An agent has enough to invoke it correctly; only a note on the expected response shape is absent, which is acceptable here.

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 the baseline is 3, but the description adds constraint semantics the schema lacks: the guest must be invited to the event and meal_choice must match an option configured on that event. This clarifies validation rules beyond the field descriptions.

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 (record) and resource (an RSVP/reply), scoped to replies received by phone or mail, and maps it to the analogous UI action ("Track RSVPs"). It reads clearly apart from siblings like zola_track_rsvps and joy_get_rsvp_summary.

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 "reply you got by phone or mail" framing tells the agent when this applies versus an online RSVP flow, and it names prerequisites (guest must be invited, meal_choice must be a set option). It stops short of explicitly naming a sibling as the alternative.

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