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

Annotations already indicate destructive and idempotent behavior. The description adds valuable context beyond annotations: clients using the key stop working immediately, authentication is required, and unknown ids return 404. This directly informs the agent of consequences and preconditions.

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?

Every sentence is purposeful and information-dense: purpose, immediate consequence, auth requirement, and error case. The core action is front-loaded, and there is 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 single-parameter destructive action with annotations covering safety and idempotence, the description covers purpose, auth, error handling, and real-world effect. Nothing essential is missing for an agent to invoke 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?

The schema already documents the id source at 100% coverage. The description adds ownership meaning ('current user's API keys') and error behavior for unknown ids, going slightly beyond the schema while remaining relevant to using the parameter correctly.

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 ('Revoke'), the resource ('API keys'), ownership scope ('current user's'), and the selection mechanism ('by id'). It is clearly distinct from the sibling create/list tools without needing to inspect them.

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 intended use is clear: revoke a specific API key belonging to the current user. It also provides useful contextual warnings (immediate effect) and error semantics, though it does not explicitly contrast with alternatives like app-token revocation.

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