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

The annotations already declare destructiveHint=true and idempotentHint=true, which the description does not contradict Section; the description does not add behavioral context beyond the fact that delivery history is deleted. There is no mention of consequences like irreversibility, permission requirements, or side effects on dependent resources. With annotations covering the safety profile, a 2 feels slightly low, but the description adds minimal behavioral detail (only the history deletion) beyond the hints, and since destructiveHint is already set, a 3 might be fair, but given the instruction to use full range and that the description does little to explain the impact, I'll assign 2 as the gap is notable.

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 sentence that is concise and to the point. It could be seen as slightly terse, but it captures the essential action and scope. It earns a 4 for being efficiently written without extra fluff.

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?

The tool is relatively simple with few parameters and an output schema, but it is a destructive operation. The description does not mention what happens in terms of reversibility or any special conditions (e.g., if the endpoint is in use). Given the presence of an output schema and complete parameter documentation, a 3 is appropriate; it is adequate but not rich.

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?

The input schema covers both parameters with 100% coverage; the description does not add any parameter-specific details. However, the schema already names the 'endpoint_id' and explains the idempotency_key thoroughly. Since schema coverage is high, the baseline is 3, and no extra value is added by the description here.

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 action (delete) and the resource (webhook endpoint), and explicitly mentions it also deletes the delivery history, which distinguishes it from other webhook operations like test_webhook_endpoint or update_webhook_endpoint. This is a specific and unambiguous purpose.

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 clearly indicates that deletion also removes delivery history, providing context on the scope of the operation. However, it doesn't explicitly contrast with alternatives (e.g., when to use update instead of delete), but the destructive nature and singular action make usage clear. Since there is no explicit 'when not to use', it scores 4 rather than 5.

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