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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is known. The description adds meaningful behavioral detail beyond annotations: it does not echo the secret and X-API-Key is only an alias. This is valuable context for an agent deciding whether the call is safe.

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 three short, purposeful clauses: what it confirms, which credentials are accepted, and the no-echo guarantee. Every sentence earns its place and the core action is front-loaded.

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 zero-parameter read-only verification call, the description is complete: it states the operation, the accepted credential forms, the alias limitation, and a key safety behavior. No invocation-critical 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 input schema is empty, so there are no parameters whose semantics need clarification; the baseline for a zero-parameter tool is 4. The description adds relevant auth context rather than parameter detail, which is appropriate.

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 uses a specific verb ('Confirm') and resource ('key'), and further specifies the API key header and Authorization form with the exact endpoint. This clearly distinguishes verification from the key lifecycle siblings like issue_key, revoke_key, and rotate_key.

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 intended use is implied: call this to confirm a key is valid rather than to create or revoke one. However, the description does not explicitly name alternatives or state when to prefer this tool over sibling key-management tools; the X-API-Key alias caveat helps prevent misuse but is not full routing guidance.

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