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

With no annotations, the description carries the full burden and succeeds. It discloses that the key will immediately stop working, that the action is irreversible, that 2FA is required, that a Proof account is needed, and that session authentication must be established first. These are meaningful behavioral facts beyond the schema.

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 front-loaded with the core action and effect, then uses labeled sections ('Agent usage', 'ACCESS') to organize prerequisites and procedure. Every sentence conveys necessary information; there is no filler or 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 single-parameter, no-output-schema tool with no annotations, this description is complete. It covers purpose, side effects, irreversibility, authentication, and the exact 2FA sequence needed before invocation. An agent has everything required to call this tool 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?

Schema description coverage is 100%, so the baseline is 3. The description's 'by ID' mirrors the schema's 'API key ID to revoke' without adding extra semantic detail, format, or source guidance. It does not harm, but it also does not improve on the schema.

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 opens with a specific verb and resource: 'Revoke an API key by ID.' This clearly distinguishes it from sibling revoke_* tools that target other resources (authorization, delegation, proof) and from create_api_key/regenerate_api_key. The scope and target are unmistakable.

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 description provides explicit, step-by-step usage guidance: complete the 2FA flow via start_2fa, wait for user verification, poll get_2fa_status, then call revoke_api_key. It also gives an authentication workflow with start_login. It does not explicitly mention when-not-to-use or alternatives, but the procedural context is strong and clear enough to place this tool correctly.

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