get_departures

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

No annotations are provided, so the description carries full responsibility for disclosing behavior. It does not mention whether the operation is read-only, whether it has side effects, or any potential failure modes. This omission leaves the agent uncertain about safety.

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 succinct and well-structured, with a clear opening sentence and a neat bullet-like list of parameters. No redundant information is included, and every word adds value.

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 that an output schema is present, the description does not need to explain return values. It provides sufficient context about the input parameters and the core functionality. However, it could mention that the output is a list of departures, but that is already implied by the purpose.

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?

The Args section covers all four parameters with concise explanations: stop_id (required, resolve names), when (optional, ISO 8601, Sydney time), platform_id (restrict), and realtime (include live delays). This provides meaningful context beyond the raw schema, though it could elaborate on edge cases or default behaviors.

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: listing upcoming departures from a stop and referring to it as the live departure board. It uses a specific verb ('List') and resource ('departures from a stop'), but does not explicitly differentiate from sibling tools like plan_trip or get_vehicle_positions.

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 by requiring stop_id and suggesting resolving names with find_stop. However, it lacks explicit guidance on when to use this tool instead of alternatives, such as when not to use it or what scenarios it is best suited for.

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