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

Annotations already disclose that the operation is non-read-only, destructive, and non-idempotent. The description adds useful behavioral context beyond annotations by stating that the new secret is returned only once, which is important for the caller to capture immediately.

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 sentences with zero filler. The core action and the one-time return behavior are front-loaded and easy to parse.

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 destructive mutation with no output schema, the description covers the action and the return behavior well. It could be stronger by explicitly noting that the previous secret is invalidated immediately, but otherwise an agent has enough context to call it correctly.

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% for both parameters, and the description adds no further meaning about parameter syntax or constraints. Baseline 3 is appropriate when the schema already documents parameters fully.

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) and resource (HMAC signing secret for an outgoing webhook endpoint). It is clearly distinguishable from sibling tools like create_webhook, delete_webhook, and list_webhooks, which do not perform secret rotation.

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 explains what the tool does but gives no guidance on when to use it, when not to use it, or what alternatives exist. There is no mention of prerequisites such as the webhook needing to exist or the old secret becoming invalid.

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