Rotate a SIP credential's password

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

The description adds significant insight beyond the destructiveHint annotation: it specifies that the old password stops working immediately, the new plaintext password is returned exactly once, and that step-up MFA is required. This fully informs the agent of the tool's behavior.

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 extremely concise: two sentences plus a list of error codes. The most critical information is front-loaded, and every sentence provides value without redundancy.

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 two-parameter tool with no output schema, the description covers all necessary aspects: purpose, behavioral impact (immediate, one-time return), security requirement (MFA), and error conditions. It is fully self-sufficient.

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%, and the description does not supplement the schema with additional parameter details. It adds no extra meaning beyond what is already in the input schema, so baseline score of 3 is appropriate.

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 clearly states the action ('Generate a new password + HA1') and the resource ('SIP credential'), explicitly noting that username and realm remain unchanged, which distinguishes it from related tools like trunk_create_credential and trunk_update_credential.

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?

While the description does not explicitly list alternatives, it provides clear context by stating the immediate effect of the old password stopping and that the new password is returned once, implying a specific use case for password rotation. The error list also guides proper invocation.

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