Test credential

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

The description discloses key behavioral traits beyond annotations: the tool contacts an external service, may log the attempt, returns only the target-bound OK/Error outcome, and withholds the upstream diagnostic message. This complements the annotations without contradiction.

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 every sentence earns its place. It covers purpose, parameter source, usage guidance, permissions, and output behavior in four sentences with no 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?

Given the simple single parameter, rich annotations, and presence of an output schema, the description is complete. It provides all necessary context for an agent to select and invoke the tool correctly, including side effects and safety considerations.

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 covers the credentialId parameter, but the description adds important semantic detail: it specifies the ID comes from credentials_list or get, and explicitly states that inline credential data, names, and types are not accepted. This goes beyond the schema's simple description.

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 clearly states the tool's purpose: testing an already stored credential by contacting its external service. It distinguishes itself from related tools like get (metadata-only) and list by specifying that inline credential data is not accepted and that it targets stored credentials.

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?

Explicit guidance is provided: 'Use get for metadata-only inspection and skip this tool when network contact is unwanted.' It also notes the requirement for unsafe mode and test permission, giving clear conditions for when this tool is appropriate.

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