head_to_head

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

No annotations are provided, so the description must carry the burden. It doesn't disclose any behavioral traits like mutability, required permissions, or data scoping. It does mention 'all key metrics' but doesn't specify what those are. However, an output schema exists, which likely details the return structure, so the lack of behavioral detail is somewhat mitigated.

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 for purpose/usage and a brief argument list. Every sentence adds value, and there is no verbose or redundant text.

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?

Given the tool has only two simple parameters and an output schema exists, the description provides enough context for an AI agent to understand when and how to use it. However, it could be slightly more complete by listing the key metrics it compares, but that may be detailed in the output schema.

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 input schema only defines parameters as type string. The description adds important semantics: 'name, code, or number' for each driver, clarifying acceptable formats. With 0% schema description coverage, the description fully compensates by explaining what values are valid.

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: 'Compare two drivers across all key metrics.' It uses a specific verb (compare) and resource (drivers), and distinguishes itself from sibling tools like driver_telemetry or fastest_laps that focus on individual drivers or specific metrics.

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 tells when to use the tool: 'when the user asks to compare drivers, wants a head-to-head analysis, or asks who was better between two specific drivers.' It doesn't provide when-not-to-use or alternatives, but the context from sibling tools implies other tools for single-driver queries.

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