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

Annotations already mark the operation as read-only, and the description consistently describes a read/list operation. It adds useful behavioral detail beyond annotations: the exact output dimensions and the conditional behavior when 'service' is supplied. There is no contradiction with annotations.

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?

Two dense sentences carry all essential information with no filler. The main scope is front-loaded, and the conditional service behavior is stated clearly and compactly.

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 simple read-only listing tool with no output schema, the description covers the major returned fields and the important service-parameter behavior. Minor gaps remain: no mention of limit semantics/defaults, pagination, or explicit distinction from get_city_rates, but these are not critical for basic correct 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?

The schema already describes 'query' and 'service'; the description adds meaningful context for 'service' by explaining that it switches the result to a per-service coverage view. However, 'limit' is not mentioned in the description, and with 67% schema coverage the description does not fully compensate for that gap.

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 resource (Russian cities with rates) and enumerates the returned data: search by name, number of services posting a rate, maximum rate ₽/hour, and presence of a city page. It also explains the conditional service-scoped mode. However, it does not explicitly distinguish itself from the closely named sibling get_city_rates, so differentiation is implied rather than stated.

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 explains what the tool does and how the service parameter changes the result, but it gives no explicit guidance on when to choose this tool over alternatives. No exclusions or sibling comparisons are provided, so an agent gets no direct routing help.

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