transport_departures

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

Annotations already indicate readOnlyHint=true and destructiveHint=false, so the description's job is lighter. The description adds value by noting real-time information including delays, and analogizing to a digital departure board, which helps set expectations beyond the schema.

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 concise: three sentences plus a bullet list. It front-loads the primary function and uses efficient language with no redundancy.

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's moderate complexity (real-time data, multiple parameters), the description covers the main purpose, prerequisite, and return fields. It does not explain all edge cases, but an output schema likely handles that. The description is sufficient for an agent to select and invoke the tool correctly.

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?

Despite schema description coverage reported as 0%, the input schema itself contains detailed descriptions for each property (e.g., stop_id, time, limit). The tool description adds little new parameter-specific meaning beyond what is already in the schema, though it does reiterate the prerequisite for stop_id.

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: 'Get upcoming departures or arrivals at a Swiss public transport stop.' It uses a specific verb+resource pattern and distinguishes itself from sibling tools by explicitly referencing transport_search_stop as a prerequisite.

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 instructs users to 'Use transport_search_stop first to get the stop_id,' providing clear usage guidance. It also implies the tool is for real-time departure boards. However, it does not explicitly state when not to use it or compare it to alternatives like transport_nearby_stops.

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