Get TTC fares

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

With no annotations provided, the description carries full burden for behavioral disclosure. It explicitly states that fares are a flat, hand-maintained table and that TTC publishes no machine-readable data, which informs the agent about data freshness and limitations. This is valuable context beyond obvious read behavior.

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 with two sentences: the first defines the tool's core purpose, and the second adds filtering options and a note about data source. Every sentence is meaningful, and there is no extraneous information.

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 the presence of an output schema (not shown), the description appropriately avoids explaining return values. It covers the main elements (fare types, transfer rule, filters) but does not mention error handling or edge cases, which is acceptable for a simple retrieval 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?

The input schema has 100% coverage with descriptions for both parameters. The description adds that filtering is optional, but this does not significantly enhance the schema's existing detail. Thus, the description provides minimal added value beyond the schema.

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 retrieves the current TTC fare table and the 2-hour transfer rule, specifying the rider categories and payment types. It uses a specific verb and resource, and although no siblings are present, the description is unambiguous about its scope.

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 mentions optional filtering by category and/or fare_type, providing clear guidance on how to use the tool. However, it does not specify when not to use it or provide alternatives, which is acceptable given the absence of sibling tools.

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