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

Annotations already flag this as non-read-only and non-idempotent, and the description adds real value on top: the proof is valid for 5 minutes, it requires the caller's key ('Needs your key'), and it exists specifically to prevent a copied link from passing verification. These are exactly the operational details the annotations cannot convey. The only gap is that it doesn't explain what happens on expiry or failure.

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?

Three short sentences, front-loaded with the situation that triggers a call. The rhetorical question opener and the 'not a copied link' justification are slight indulgences, but they earn their place by conveying the security intent efficiently.

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 non-idempotent, non-destructive action with fully documented parameters and no output schema, the description supplies the missing pieces an agent needs: auth requirement, a 5-minute validity window, and a qualitative statement of the return value ('returns a holder proof'). Expiry/error behavior would make it complete.

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 both parameters are self-documented there, including 'exactly as given' for nonce. The description reinforces the nonce's role in the flow but never mentions the optional audience parameter, so it adds only marginal meaning over the schema. Baseline 3 applies.

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?

States a concrete action: it returns a holder proof where PazAIr signs the caller's agent id with a supplied nonce. That is specific enough to distinguish it from get_pass or check_word_pass, though it never names those siblings explicitly and instead relies on the scenario preamble ('Another agent checking your Word Pass gave you a nonce?').

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 opening scenario ('Another agent checking your Word Pass gave you a nonce?') implies the trigger condition for calling this tool, which is useful. But it offers no explicit when-not guidance and does not point to alternatives such as check_word_pass, verify_pass, or get_pass, so routing between the several word-pass siblings is left to inference.

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