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

Annotations already declare destructiveHint=true, idempotentHint=true, readOnlyHint=false, so the safety profile is covered; the description adds real value by naming the concrete side effect — the signing secret is invalidated and the action is irreversible. It stops short of stating what happens to in-flight/queued deliveries or auth requirements, but that is a minor gap given the annotation coverage.

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 clauses with the irreversible consequence front-loaded immediately after the action. Zero filler and nothing to trim.

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 destructive tool with no output schema, the description supplies the action, the effect, and the irreversibility warning — enough to call it safely. Only marginal items (behavior on an already-deleted webhook, permission requirements) are absent.

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?

One required parameter with 100% schema description coverage, so the schema already carries the parameter burden. The description adds no format, sourcing, or lookup guidance for webhookId, so the 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?

Specific verb+resource ('delete a webhook subscription') with a clarifying parenthetical that states the observable effect ('stop receiving its deliveries'). That effect wording makes it easy to tell apart from update_webhook and verify_webhook without opening either 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?

The stated effect implies when the tool is appropriate, but there is no explicit when-to-use, no prerequisite (e.g., confirming the webhook exists), and no routing to alternatives such as update_webhook for partial disablement. Usage must be inferred.

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