find_cheapest_gas_stations_on_route

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

Annotations already declare readOnly, idempotent, non-destructive, and closed-world, so the safety profile is covered. The description adds genuine behavioral context beyond that: the route is sampled, a 1km radius search is run per sample point, and results are capped at the top 5 cheapest. It lacks detail on rate limits or sampling granularity.

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?

Front-loaded with the core action and scope in the first sentence, then args and returns. The structure is clean and each line carries content, though the Args/Returns framing is slightly verbose for a four-parameter tool.

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?

No output schema exists, yet the description spells out the return shape (route_info with distance_km/duration_min, and gas_stations with name/brand/price/distance), and all four parameters plus the sampling behavior are documented. An agent has everything needed to call and interpret the result.

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%, so the description must carry the parameter burden, and it does: origin/destination with examples, fuel_type with the actual code values (B027, D047, K015, C004) mapped to fuel names, and priority with its three allowed values and default. This is information the schema does not encode.

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?

States a specific verb and resource (finds cheapest gas stations) plus a scope qualifier ('along a route') that separates it from the sibling find_cheapest_gas_stations_nearby. An agent can distinguish it from get_route as well, since the returned entity is stations, not a route.

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?

Usage is implied by the name and scope – use this when you have an origin and destination and want stations along the path – but there is no explicit when-to-use/when-not guidance and the sibling find_cheapest_gas_stations_nearby is never mentioned, even though choosing between the two is the main routing decision.

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