get_fare_estimate

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

With no annotations, the description carries the burden of behavioral disclosure. It mentions the dependency on prior location setup, which is a useful behavioral trait. However, it does not describe what happens if locations are not set, nor any details about the output format or side effects, leaving some ambiguity.

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 extremely concise, consisting of two short sentences that convey purpose and prerequisite without unnecessary words. It is front-loaded with the action verb and resource.

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 zero-parameter stateful tool, the description covers the essential purpose and prerequisite. It does not elaborate on return values, but since there is no output schema and the tool appears simple, this is adequate. It might benefit from noting what happens when locations are unset, but overall it is reasonably complete.

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 tool has zero parameters, so the baseline is 4. The description adds context by referencing 'current pickup and destination,' which clarifies that the tool uses existing state rather than requiring input parameters.

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 fetches fare estimates based on the current pickup and destination, which is a specific verb-resource pairing. It does not explicitly differentiate from sibling tools like get_ride_options, but the scope is clear enough for basic selection.

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 the tool is used after setting pickup and destination, and states the prerequisite 'Both locations must be set first.' However, it does not provide any comparison or exclusion regarding alternative tools such as get_ride_options, so guidance on when to use this versus alternatives is lacking.

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