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

Annotations only include readOnlyHint=false and destructiveHint=false, which are not very informative. The description compensates by stating 'Creates a DRAFT only — it does not publish, charge, or contact anyone', which clarifies non-destructive behavior and side effects. It also notes that if an image is passed, Lemonvite downloads and stores it permanently, which is important behavioral context. Missing details on rate limits or idempotency but given the draft-only nature, this is sufficient.

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 description is a single, dense paragraph that front-loads the core purpose and then clarifies boundaries slash use cases. Every sentence adds value: trigger conditions, draft behavior, when not to call, and which fields are essential now. It is long but justified given the 25-parameter surface and need to prescribe usage; no fluff detected.

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?

Given the 25 parameters and nested objects, the description covers the essential decisions: what is required, what can be deferred, how image handling works, and how this differs from update. The output schema exists, so return value documentation is not needed. The description is complete enough for an agent to invoke correctly without ambiguity.

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 high at 84%, meaning most parameters are described in the schema. The description adds value by emphasizing which fields are required at creation (title, event_type, start_datetime, timezone) and which can be added later, plus special notes like location_name being required for in-person events and host_name needed when account has no display name. This goes beyond the schema's individual descriptions to guide overall usage.

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?

The description clearly states the tool creates a Lemonvite invitation from an event plan, listing specific trigger phrases and the key capability of turning an image into an invitation. It distinguishes itself from mere discussion and from the update tool by explicitly mentioning the draft state and pointing to lemonvite_update_invitation for additions. This is a specific verb+resource with clear scope.

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 explicitly says when to use it (when the user wants an invitation/RSVP page to exist) and when not to (merely discussing wording/images). It also distinguishes from lemonvite_update_invitation by noting that most fields can be added later, and implies that other actions like publishing are separate (lemonvite_publish_invitation). This is explicit and actionable guidance.

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