map_match

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

Despite no annotations, the description discloses key behaviors: output structure (matched_points, confidence, geometry), coordinate ordering criticality, minimum points, and recommended sampling rate. It does not cover side effects or authentication needs, but the disclosed details are substantial for a map-matching tool.

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 well-structured: purpose first, then return details, then a clearly marked coordinate warning, followed by requirements and use cases. It is slightly verbose but remains focused and easy to parse. All sections serve a function.

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 absence of an output schema, the description provides the full return shape and useful context about coordinate ordering and usage. It could clarify the 'confidence' scale or mode effects, but overall it covers the essential aspects for correct invocation.

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?

With 100% schema coverage, the schema already documents both parameters. The description adds value by emphasizing the coordinate order with a critical warning, examples, and explanations of correct vs. wrong usage. For the 'mode' parameter, it does not add beyond the schema, but the coordinates enrichment justifies a score above baseline.

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 opening sentence clearly states the tool's function: 'Snap a raw GPS trace to the road network to correct GPS drift and determine the actual route taken.' This provides a specific verb and resource, effectively differentiating from siblings like nearest_road (which handles single points) or route (which computes optimal paths).

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 includes 'USE FOR: Fleet tracking post-processing, trip analysis, mileage calculation, delivery verification' and gives minimum point requirements, but does not explicitly compare to sibling tools or state when not to use. Usage context is implied rather than directly contrasted with alternatives.

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