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

Goes well beyond the annotations: discloses partial-update semantics ("whatever you leave out stays as it was"), that re-enabling resets the failure count to zero, and the operational prerequisites (API key, paid plan, costs no credits). The destructiveHint=true annotation is not contradicted – the endpoint can be switched off.

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 short sentences, front-loaded with the capability summary, then the reactivation workflow, then state semantics, then prerequisites. No filler and no repetition of schema content.

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 4-parameter partial-update tool with no output schema, the description covers capability, state semantics, reactivation workflow, and auth/billing prerequisites. An agent can call it correctly without opening anything else.

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 75%, and the description still adds meaning on top: it maps rename to the description field and explains the state transition and side effect of enabled=true that the schema's one-line note doesn't fully convey. The id parameter and event enum semantics are left entirely to the schema, which is acceptable.

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 plus the three mutable facets (events, name, enabled), so an agent immediately knows this is a partial update of an existing webhook. It never names create_webhook or delete_webhook, so sibling routing rests on inference, but the scope is unambiguous.

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 a concrete when-to-use scenario: reactivating an endpoint after deliveries were stopped by fixing the server and setting enabled to true. That's stronger than generic context, though it never states when NOT to use it (e.g., to change the target URL, use delete+create).

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