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

Annotations already declare idempotentHint=true, readOnlyHint=false, destructiveHint=false and openWorldHint=true, but the description adds genuinely new context: the required webhook.manage permission, the asynchronous queue-vs-HTTP distinction, the tenant/agent/Live-Sandbox authorization model inherited from /api/v1/webhooks/endpoints, and an idempotent-retry protocol. That is materially more than the annotations convey.

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?

Front-loaded with the purpose and the queue-vs-delivery caveat, and every sentence carries operational content. It is dense with five clauses, but none are pure filler; the docs URL and authorization-model sentence are slightly less essential than the rest.

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?

An output schema exists, so return values need no explanation, and the three parameters are fully documented in the schema. The description closes the remaining gaps an agent would care about: permission requirement, async semantics, retry safety, and where to observe the result.

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 baseline is 3; the description adds a small amount beyond the schema by framing idempotency_key reuse in terms of 'an uncertain mutation' and pointing endpoint_id back to list_webhook_endpoints. It does not explain expected_revision's optimistic-concurrency role, which the schema already covers well.

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?

Precise verb+resource+scope: 'Queue a synthetic webhook.test delivery (no item) to check the receiver and its signature verification.' The '(no item)' qualifier implicitly separates it from the sibling test_webhook_endpoint_with_sample, and 'synthetic ... delivery' separates it from create_webhook_endpoint.

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?

States the when-not explicitly ('Queue admission is not HTTP delivery') and routes the agent to the correct verification path via list_webhook_deliveries. It also gives retry guidance ('Reuse the exact idempotency_key and input after an uncertain mutation'), so the agent knows both the trigger and the follow-up tool.

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