Calculate Route

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

Annotations already declare readOnlyHint and openWorldHint, so the bar is lower. The description adds useful behavior beyond those flags: it returns distance, duration, turn-by-turn directions, toll information (car/caravan only), and optional alternative routes. This communicates mode-dependent behavior and response content without contradicting the annotations.

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 compact and front-loaded: the core purpose appears first, followed by concrete format guidance and a prerequisite. Every sentence earns its place without redundant restatement of the tool title or schema.

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?

For a read-only route calculation tool with no output schema, the description covers the essential prerequisites, coordinate format, supported modes, and return contents. The rich input schema fills in parameter-level details like routeType and avoid options, so nothing critical is missing.

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 100%, so the schema already documents every parameter. The description adds a clear coordinate-pair example and the find_locations workflow, but it does not materially deepen the meaning of parameters beyond what the schema already provides.

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 a specific action ('Calculate a route'), the resource ('between two or more locations using ANWB route planning'), and the supported modes (car, caravan, bike, pedestrian). This makes it straightforwardly distinct from siblings like calculate_ev_route or get_traffic_summary, even without naming them.

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?

It gives explicit practical guidance to 'Use find_locations first to get coordinates for place names', and clarifies supported travel modes. It does not explicitly say when to prefer calculate_ev_route over this tool, but the mode list and ANWB context give a clear usage envelope.

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