rotate_api_key

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

Goes well beyond the annotations (destructiveHint, idempotentHint=false, openWorldHint) by disclosing non-obvious behavior: the new secret is returned once and is exposed to the MCP transcript, and the previous secret stays valid until key_transition_expires_at. The one-time-return and grace-window semantics are exactly the traits an agent cannot infer from structured fields.

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?

Compact and front-loaded: the rotation action and its identity-preserving property come first, followed by the secret-exposure warning and the transition-window lifecycle. Every clause carries information, though the security admonitions are slightly dense for a single paragraph.

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?

With an output schema present, return values needn't be spelled out, and the description still flags the critical one-time secret return. Combined with annotations covering the destructive/non-idempotent profile, an agent has enough to call it safely; only explicit sibling routing is missing.

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 both parameters are fully documented there, so the schema carries the semantic load. The description references the transition window concept (key_transition_expires_at) but adds no syntax, units, or bounds beyond what the schema already states (minimum 1,800,000 ms).

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?

States a specific verb+resource ('Rotate an API key') and adds a distinguishing scope constraint ('without changing its identity or scopes'), which separates it from update_api_key and create_api_key. It does not name those siblings explicitly, so the differentiation requires a small inference.

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?

Gives operational guidance during the rotation (store the new key securely, update callers during the transition window, never log secrets), which implies the intended workflow. However, it never states when to choose rotation over update_api_key/create_api_key, nor prerequisites such as required permissions.

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