Track a 99 ride

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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint false, covering the safety profile. The description adds behavioral constraints that the tool only works on active rides and excludes GPS/driver phone data, which goes beyond annotations. However, it does not describe error behavior or what occurs when no active ride exists, a minor gap.

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 extremely concise: two sentences, front-loaded with the primary purpose and followed by explicit exclusions. There is no redundant wording, and every sentence adds value. The structure is efficient and easy to parse.

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 3-parameter tool with no output schema, the description is incomplete. It does not explain the meaning of privacy_mode or response_format, nor does it describe the expected response structure or error conditions. Since the output schema is absent, the description should provide more detail on what the agent will receive, but it only gives broad categories (status, ETA, category).

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%, and the description does not mention any of the three parameters. The schema provides enums for privacy_mode and response_format, but no descriptions of their meaning or effect. The description fails to compensate for the lack of schema documentation, leaving the agent to infer parameter semantics from names alone.

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 returns 'Active ride status/ETA/category only' and explicitly excludes 'GPS polylines or driver phone,' which effectively distinguishes it from sibling tools like ninenine_ride_history and ninenine_active_ride. While the verb is not explicit, the title 'Track a 99 ride' implies tracking, and the scope is unambiguous.

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 implies usage for active ride status by using 'only,' but it does not name sibling alternatives or provide explicit conditions for when to choose this tool over others. There is no mention of when not to use it or reference to tools like ninenine_estimate or ninenine_ride_history, leaving the agent to infer the use case.

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