get_connections

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

No annotations are provided, so the description carries the transparency burden. It reveals a useful behavior: 'Station names are resolved by the upstream API, so common spellings work directly.' It also implies a temporal scope via 'upcoming' and 'from now.' It does not disclose error handling or limits beyond schema, but for a read-only tool, this is adequate.

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 two concise paragraphs. The first sentence states purpose; the second provides usage context and examples. Every sentence earns its place, with no redundancy or filler. Structure is front-loaded with the core 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?

With 5 parameters and an output schema present, the description sufficiently covers purpose, usage scope (Switzerland), and a key behavioral quirk (station name resolution). It does not describe potential failure modes or return value structure, but the output schema likely handles that. Minor gaps exist but are not critical given the tool's simplicity.

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 baseline is 3. The description adds value by explaining that station name parameters accept common spellings, reducing ambiguity for from_station and to_station. The examples also illustrate how date/time interpret relative requests, though schema already covers syntax. Overall, it enhances parameter understanding beyond the schema.

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 starts with a specific verb and resource: 'Find upcoming train, tram, bus, or boat connections between two stations.' It clearly distinguishes the tool's scope from sibling tools like get_stationboard (which likely focuses on a single station's departures) by emphasizing connections between two named places.

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?

Explicitly states when to use the tool: 'Use this tool when the user asks for travel options between two named places in Switzerland' with concrete examples. It also clarifies that station names are resolved upstream, preventing unnecessary pre-resolution via find_station. No alternatives are mentioned, but the guidance is clear and actionable.

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