swiss_transport_connections

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It only mentions 'No API key needed,' which is useful but insufficient. It doesn't describe what the response contains, how connections are ordered (by departure time?), whether results are limited by the 'limit' parameter, or any rate-limit or error behaviors. The 'via' and 'datetime' parameter behaviors are not disclosed at all.

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 concise sentence that immediately conveys the core purpose ('Find train/bus connections between two Swiss locations') and the key operational detail ('No API key needed'). It's efficient with no filler, though it could add a bit more behavioral context without becoming bloated.

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?

This is a moderately complex multi-parameter tool (5 params, 2 required) with no annotations and no output schema. The description provides only the basic purpose. Given the sibling swiss_set_api_key tool and the mention of 'No API key needed', the description partially positions this against tools that DO require keys, but it lacks essential context: result ordering, pagination, error handling for invalid location names, and how 'via' affects routing. For a tool of this complexity with zero annotation coverage, more detail is needed.

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 80%, with most parameters (from, to, via) having descriptions in the schema. The description adds no parameter-level detail beyond what the schema already provides. The 'limit' parameter has schema constraints but the description doesn't clarify whether the default of 3 connections is reasonable or how limit interacts with via routing. At 80% coverage, the baseline 3 is appropriate.

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 'Find train/bus connections between two Swiss locations' — a specific verb+resource+geographic scope. It clearly distinguishes from sibling tools like swiss_transport_station_search (station lookup) and swiss_transport_stationboard (departures from a single station) but does not explicitly name these 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 implies usage for point-to-point journey planning between two Swiss locations, which distinguishes it from stationboard (single-station departures) and station_search (station lookup). However, there are no explicit when-to-use vs when-not-to-use statements or named sibling alternatives, and no guidance about whether 'locations' must be station names, addresses, or both.

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