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

Annotations cover the safety profile (destructive, idempotent, not read-only). The description adds valuable context beyond that: 'The key stops working immediately', telling the agent about propagation timing. Not a full 5 since reversibility and auth requirements aren't addressed.

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 short sentences, front-loaded with the action verb and resource, second sentence adds the critical behavioral note. Zero waste.

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?

Adequate for a single-param destructive mutation tool with annotations carrying the safety profile and a schema documenting the parameter. Missing only edge-case behavior (e.g., what happens if the key doesn't exist or is already revoked), but the essential information is present.

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 coverage is 100%, so the param is already documented including the 'from list_api_keys' hint. The description reinforces 'by its ID' which is consistent, but adds no new syntax or format details. Slightly above baseline due to reinforcement of the identifier semantics.

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: 'Revoke (deactivate) a REST API key by its ID'. Clearly distinguishes from siblings like delete_mcp_key and delete_byok_key by scoping to REST API keys, and matches the name exactly.

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?

Implies usage through 'by its ID' and the schema notes 'from list_api_keys' which hints at the list-then-revoke pattern. But no explicit when/when-not guidance or alternatives (e.g., vs delete_mcp_key) are given.

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