Book a Waymo ride

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

The description says 'Book', which implies a state-changing mutation, while annotations declare readOnlyHint=true. This is a direct contradiction. The description also does not disclose side effects such as creating a reservation or payment implications.

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 short, purposeful sentences. It front-loads the core action and then gives the key invocation rule without any filler.

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 is minimally sufficient for tool selection: it identifies the booking action and when to call. However, it omits important behavioral context like side effects, and the contradictory readOnlyHint annotation undermines the overall reliability of the definition.

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 descriptions already cover proposal_token and payment_method_id, giving 67% coverage. The description adds little parameter-specific detail, though 'quoted ride' and the explicit-request condition provide indirect context for the confirmation field.

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 clear action ('Book') and resource ('a quoted ride'), making the tool's purpose obvious. It also separates this from siblings like waymo_get_quote and waymo_cancel_ride, though it does not explicitly name alternatives.

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 gives an explicit trigger condition: call only after the user explicitly requests booking. It does not describe exclusions or alternatives, but the sibling set makes the intended workflow reasonably clear.

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