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

Beyond the annotations (readOnlyHint=false, idempotentHint=false, destructiveHint=false, openWorldHint=true), the description discloses that auth is required, that a signed POST is sent and the tool waits for the response, that a disabled hook returns 409 webhook_disabled and sends nothing, and that it fails with 404 webhook_not_found. This is exactly the additional behavioral context annotations cannot carry.

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 usage condition is front-loaded, followed by auth requirement, inputs, payload shape, return shape, and error codes in a compact sequence. Every sentence earns its place; nothing is padded or redundant.

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 no output schema, the description carries the return contract (delivery object with id, status, response_status, attempts, event_id; status delivered/failed) plus the failure modes (409, 404). For a single-parameter side-effecting test tool, nothing an agent needs to call it correctly is missing.

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 description coverage is 100% and there is only one parameter, so the schema already documents webhook_id as the wh_… identifier. The description repeats 'webhook_id (required)' and shows it embedded in the payload, which adds framing but no meaning beyond the structured data. Baseline 3 applies.

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 states a specific verb and resource — confirm a webhook URL accepts a signed POST right now — which is unambiguous and distinguishable from siblings like register_webhook, update_webhook, or rotate_webhook_secret. An agent knows exactly what this tool does without opening the schema.

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?

It gives an explicit trigger condition: 'Use this when you need to confirm a webhook URL accepts a signed POST right now.' That is clear context for when to invoke it. It does not name alternative tools or state when not to use it (e.g., versus register_webhook), so it stops short of a 5.

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