find_routes_between_stops

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

No annotations provided, so description carries the burden. It adds behavioral context: stops can be specified by NaPTAN code or name substring. It does not detail error handling or return format, but for a query 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 efficiently structured: one sentence for purpose followed by a clear parameter list. No unnecessary words, front-loaded with the main action.

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 only 2 required parameters, no annotations, and an output schema exists, the description is largely complete. It covers purpose and parameter semantics. Minor lack of info on output or error handling, but not critical for this simple tool.

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 0%, but the description adds meaningful parameter descriptions: 'Stop A' and 'Stop B' with format details (NaPTAN code or name substring). This compensates for the schema's lack of descriptions.

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: 'Find all bus routes that serve BOTH of the given stops.' The verb 'find' and resource 'bus routes' are specific, and the condition 'BOTH' distinguishes it from sibling tools like find_buses_by_arrival_time or get_route_stops.

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 on when to use the tool (when needing routes serving both stops). However, it does not explicitly mention when not to use it or suggest alternatives like plan_journey or get_route_stops.

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