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

Annotations already declare destructiveHint=true, and the description adds value by specifying the consequence: the old secret is invalidated and verification logic must be updated. This goes beyond the annotation by explaining the operational impact.

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 two sentences with zero waste. The core action and return value are stated first, followed by a critical operational instruction. Efficient and front-loaded.

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 simple one-parameter tool with no output schema, the description covers the action, the return value, and the essential post-action. Annotations cover the destructive nature, and no further information is needed for correct invocation.

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% for the single parameter webhookId, and the description does not add any additional semantic detail beyond the schema's 'Unique identifier of the webhook'. Baseline 3 is appropriate as the schema carries the full burden.

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 ('rotate'), resource ('webhook'), and the exact attribute ('HMAC signing secret'). It also mentions the return value and a required post-action, clearly distinguishing it from sibling tools like register_webhook or delete_webhook.

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 explicitly instructs the user to update verification logic immediately after rotating, which implies the old secret becomes invalid. It does not explicitly state when to use this tool versus alternatives, but the context (sibling tools) makes it the only rotation option, and the instruction is clear.

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