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

With no annotations, the description carries the full burden and does so well: it discloses tier/plan-dependent field gating and detailed error semantics (410 Gone with id and cancelledAt for removed events; 404 for unknown, unpublished, or out-of-window ids). It stops short of explicitly stating the read-only/side-effect-free nature or any auth/rate-limit behavior.

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?

Three sentences, each earning its place: purpose first, then plan-dependent behavior, then the two distinct error contracts. No filler, and the core action is front-loaded.

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 single-parameter read tool with no annotations and no output schema, the description covers purpose, access gating, and the notable failure modes an agent must handle. It does not sketch the returned payload shape, though 'full event payload' plus the 410 variant give enough of a contract for correct invocation.

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?

There is only one parameter and schema description coverage is 100%, so the schema already explains the id fully, including its source endpoint. The description's 'by id' adds no format, syntax, or constraint beyond what the schema provides, making the baseline 3 correct.

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 ('Returns the full event payload by id'), which cleanly separates it from the sibling list tools (list_events, list_event_cancellations) that return collections. An agent can tell instantly that this fetches exactly one record keyed by id.

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?

Usage is only implied: fetch a known event by id. The description never says when to prefer this over list_events or how to obtain a valid id (that hint lives only in the schema's 'as returned by GET /v2/events'). No alternatives or exclusions are named, so this is minimum-viable routing guidance.

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