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

The description discloses critical behavioral traits beyond the annotations: it rechecks availability, releases any previous selection, creates a temporary hold, returns the protected booking schema, and explicitly does not create a booking. These side effects are essential for the agent to understand the non-read-only, state-changing nature of the operation.

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 with no filler. The usage restriction is front-loaded, followed by a compact sequence of behaviors and a final clarifying exclusion. Every sentence adds value.

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 conveys the workflow and output shape well, and the output schema covers return values. However, all four input parameters are required and undocumented in both schema and description, so the agent cannot reliably construct a valid request. The missing semantics for expected_state_version and idempotency_key make the definition only minimally 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 description coverage is 0%, so the description must compensate for the four required parameters. It only implicitly maps option_key to 'one exact provider option' and gives no meaning for request_id, expected_state_version, or idempotency_key. This is a significant gap for correctly invoking the tool.

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 states a precise verb and resource: selecting one exact provider option from the final protected card. It lists specific actions (rechecks availability, releases previous selection, creates temporary hold, returns booking schema) and explicitly disambiguates from create_service_booking by saying it does not create a booking.

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?

It gives an explicit when-to-use condition: 'Use only from the final protected card when the user selects one exact provider option.' It also provides a when-not by clarifying it does not create a booking. However, it does not directly name alternative sibling tools, so guidance is clear but not exhaustive.

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