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

The description discloses that the tool is idempotent, which matches the idempotentHint annotation, and adds the behavioral nuance that header-authenticated callers do not need it. It does not contradict the readOnly=false annotation, as confirming persistence implies a state-changing action. While it repeats the idempotent hint, it adds context about conditional usage, so it is more transparent than just 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 two sentences long, with the primary purpose stated first, followed by the usage requirement and the idempotent/exception note. It is concise, direct, and well-structured with no superfluous wording.

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?

The description provides the essential context: the tool's purpose, when it is required, that it is idempotent, and who does not need it. While it does not describe the output, an output schema exists (mentioned in context) and the description is sufficient for an agent to decide when to invoke it. It is slightly lacking in explaining what the confirmation entails, but overall it is contextually complete for the tool's role.

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 tool has zero parameters and the schema description coverage is 100% (trivially). The description does not add any parameter-specific semantics because there are none to describe. Per the rubric, with high schema coverage and no added parameter info, the baseline score is 3.

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: to confirm that the user has persisted the once-shown api_key, owner_key, and wallet_private_key from register. It uses a specific verb 'Confirm' and identifies the exact objects and origin, leaving no ambiguity about what the tool does.

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 description explicitly states when the tool is required: 'Required on an upgraded guest session before money tools (hire_and_execute, escrow, withdraw).' It also provides a clear alternative condition: 'header-authenticated callers do not need this.' This gives the agent precise guidance on when to use or skip the tool.

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