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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint and destructiveHint=false, so safety behavior is covered. The description adds useful context about what a tariff record contains (surcharges, flat fares, tipping custom, source attribution), but says nothing about coverage limits, rate limits, or freshness of the official source.

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?

A single front-loaded sentence naming the resource, followed by a readable enumeration of returned fields. The list is long but each item is a distinct piece of tariff data, so little waste.

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?

With no output schema, the description's enumeration of tariff components (starting charge, per-mile rate, waiting rate, time-of-day tariffs, extras, flat fares, tipping) effectively documents the return shape. What remains missing is differentiation from sibling fare tools.

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 coverage is 100% and the single city parameter is fully documented in the schema, including the list_cities reference and examples. The description adds nothing about the parameter, so the baseline 3 applies.

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 names a specific resource (a city's official taxi meter tariff) and enumerates its contents, so the agent knows exactly what data comes back. It does not, however, distinguish this from close siblings like fairfare_check_fare or fairfare_estimate_fare, which also concern taxi pricing.

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?

There is no when-to-use guidance, no mention of prerequisites beyond the schema's pointer to list_cities, and no routing to alternatives such as estimate_fare or check_fare. The agent must infer the distinction between 'look up the tariff' and 'check/estimate a fare' on its own.

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