calculate_fare

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It states the outputs are based on 'authoritative stage charts' but does not describe what the return value looks like, how ambiguous stop names are handled, what happens when bus_number is omitted, or any side effects. The lack of such details makes it thin for a tool with no annotation coverage.

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 a single, well-structured sentence that front-loads the core function and scope. Every phrase serves a purpose, with no redundancy or filler. It is appropriately sized for the information it conveys.

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?

Despite having a moderate parameter count and no output schema, the description omits essential context: it does not clarify what the tool returns (e.g., fare amount, breakdown by class), how it handles multiple stops with the same name, or the effect of the optional bus_number parameter on the calculation. An agent would need to infer these details, making it incomplete for reliable invocation.

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 all three parameters. The description adds no additional parameter-specific meaning beyond mentioning service classes, which are not directly tied to any parameter. Per the baseline rule, with full schema coverage, a score of 3 is appropriate; the description neither enhances nor detracts from parameter understanding.

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 specific verb ('Calculate') and resource ('official TNSTC stage fare') with a defined scope (boarding and alighting bus stop in Madurai across specified service classes). It distinguishes itself from sibling tools like search_bus_routes and get_bus_details by focusing on fare calculation, so an agent can readily identify its unique purpose.

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 for fare calculation but does not explicitly state when to use this tool over siblings. There are no exclusions or explicit alternatives mentioned. An agent could infer from context, but the guidance is not explicit, so it scores at the implied level rather than clear context.

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