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

Annotations already declare readOnlyHint=false, idempotentHint=false, and destructiveHint=false, so the mutation and non-idempotency profile is covered structurally. The description adds genuinely useful context beyond that — 'return it once' warns the agent the secret is not retrievable later. However, it omits the key operational consequence of rotation: that the previous secret is immediately invalidated.

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?

A single sentence that is front-loaded with the action and includes only one additional clause, the one-time return. Every word earns its place with no filler.

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 mutation tool with no output schema, the description covers the essential mechanic (rotate, return once) but leaves out the invalidation effect on the existing secret and any detail about the subscriptionKey argument. Adequate but with clear gaps for a security-sensitive operation.

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% and there is one required parameter (subscriptionKey) whose meaning is not elaborated anywhere. The description says nothing about which webhook subscription is targeted or what form the key takes, so it fails to compensate for the documentation gap.

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: 'Rotate a webhook signing secret' is unambiguous and clearly distinct from siblings like evidence_list_webhooks, evidence_create_webhook, and evidence_set_webhook_status. It stops short of explicitly naming an alternative, but the action is unique enough among siblings that confusion is unlikely.

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?

No when-to-use guidance, no prerequisites, and no reference to sibling tools. The agent is not told when rotation is appropriate (e.g., compromised secret, scheduled rotation) or what happens to the prior secret.

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