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

Annotations already declare destructiveHint=true and idempotentHint=true, so the safety profile is covered. The description adds genuinely new behavioral context the annotations do not: the required permission level (`full_access` API key) and the underlying endpoint/method. It stops short of saying the deletion is permanent or what happens to in-flight deliveries.

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?

Two short sentences with the action front-loaded and the access prerequisite immediately after. The parenthetical operationId and service name are marginally useful for debugging but add little for tool selection.

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 deletion tool with full annotation coverage, the description covers what an agent needs: what it destroys, what credentials are required, and the backing endpoint. Lack of return-value information is acceptable since there is no output schema and the operation is a simple delete.

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 0%, so the burden is on the description. The endpoint form `DELETE /webhooks/{id}` does implicitly identify `id` as the path identifier of the webhook to remove, but no format, sourcing, or error behavior is explained beyond that.

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 ('Delete a webhook'), which unambiguously separates it from the many sibling delete_* tools (delete_contact, delete_domain, etc.) by resource. It is essentially the title restated, so it earns clarity through noun precision rather than added detail.

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 'Requires a `full_access` API key' line functions as a precondition, which is useful usage guidance, but there is no explicit when-to-use/when-not or mention of alternatives such as update_webhook or cancel/pause flows. Usage is only implied by the verb.

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