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

The annotations already provide destructiveHint=true, so the description does not need to re-establish destructiveness. It adds 'permanently', conveying irreversibility, but it does not disclose broader consequences such as invalidating active integrations or inability to restore the key. No contradiction exists.

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 a single sentence that directly states the operation with no filler or redundant clauses. It is appropriately sized for a simple, one-parameter destructive tool.

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 one well-documented parameter, a destructive annotation, and an output schema, the description is nearly complete for safe invocation. The main missing piece is explicit guidance contrasting this with revoke_api_key, which would make it fully self-contained.

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%, and the schema already documents the single id parameter clearly, including its provenance from list_api_keys. The description adds no parameter-level information, but it is not required given the complete schema coverage.

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 names a specific resource ('API key') and a specific action ('permanently delete'), and the word 'permanently' distinguishes it from the sibling revoke_api_key. An agent can tell exactly what this tool does without opening the schema.

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 permanence of the deletion implies when this tool is appropriate, but the description does not explicitly compare it to revoke_api_key or state when to choose one over the other. It leaves the important selection between delete and revoke to inference.

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