Find stop places near a coordinate

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

With no annotations provided, the description must carry the burden of behavioral disclosure. It correctly states the tool performs reverse geocoding and returns distances, which is fundamental behavior. However, it does not address edge cases, result ordering, or any limitations (e.g., geographic scope of Entur data), leaving some behavioral aspects implicit.

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 a single sentence with a clear purpose followed by a practical usage note. It is front-loaded with the core function and contains zero redundant words or 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 adequate for an agent to call the tool correctly: it specifies coordinates, mentions optional parameters exist (implicitly via schema), and tells the agent how to use the output (with departure/trip tools). It lacks an explicit explanation of the output format, but the absence of an output schema and the simplicity of a stop list make this acceptable.

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 coverage is 100%, so the schema already documents all four parameters with descriptions and ranges. The tool description adds no extra semantics beyond what the schema provides (e.g., it does not elaborate on how radius_m or max_results affect results). This meets the baseline for high schema coverage.

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 specific verb ('Reverse-geocode') and resource ('nearest public transport stop places'), and clarifies the output includes distance. It also distinguishes from sibling tools like find_addresses_near and find_place_names_near by focusing on public transport stops, and mentions the downstream use of returned IDs, making its purpose distinct.

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 provides clear context by stating 'Use the returned IDs with the departure and trip tools,' which tells the agent when this tool is relevant. However, it does not explicitly exclude alternatives or mention when not to use it, though the focus on stops implies differentiation from address/place tools.

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