Test an API key

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

Beyond the annotations, the description discloses meaningful behavior: a successful provider probe activates the key, while auth, quota, and network failures keep it out of the runtime pool. It also states the return value is a sanitized validation result plus updated metadata, which is useful context. There is no contradiction with the annotations.

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 compact and front-loaded, with the core action in the first sentence. The trailing 'Write; idempotent' duplicates annotation flags and adds a small amount of redundancy, but it does not significantly detract from the overall clarity.

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 only two simple parameters and no output schema, the description fully covers what an agent needs to call the tool correctly: the action, the key ID targeting, success/failure behavior, and the return value. No essential contextual information 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?

The schema already documents both keyId and projectId with 100% coverage, so the description is not required to add much. It only refers to 'by key id', which mirrors the schema's keyId description and adds no new parameter-level meaning.

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 starts with 'Re-test one pooled BYOK credential by key id', giving a specific verb, resource, and scope. It clearly distinguishes this from sibling tools like add_byok_key, remove_byok_key, and list_byok_keys by focusing on the testing/activation action.

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 phrase 'Re-test one pooled BYOK credential' implies the tool is for existing pooled keys, and the outcome descriptions offer behavioral context. However, it never explicitly states when to prefer this over siblings such as add_byok_key or activation_status, and it provides no exclusionary or alternative guidance.

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