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

With no annotations, the description must carry the safety and behavior disclosure. It does add a behavioral detail—the date of the last check—and the phrasing implies a read-only aggregation, but it does not explicitly state that it has no side effects, nor does it mention authorization or rate-limit considerations. For an apparent query-only tool this is adequate but not thorough.

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 entire description is one compact sentence with no filler or repetition. Every clause adds a distinct piece of information, and the main purpose ('Counts and prices across all places') is front-loaded, making the tool's function immediately obvious.

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 absence of a schema and annotations, the description serves as the full contract and enumerates most expected output dimensions, including a freshness timestamp. It falls just short of specifying the output's structure (e.g., object vs list, currency, or exact breakdown of 'by kind'), which an agent might need for reliable parsing, but it is largely sufficient for a zero-parameter aggregation 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 tool has zero parameters and an empty input schema, so the description is the sole source of meaning beyond the structured schema. It goes well beyond the baseline by detailing what the output covers (counts, pricing modes, price range, median, link types, kind, freshness), adding substantial semantic value where the schema provides none.

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 verb ('Counts and prices') and a clear resource ('across all places'), then enumerates the dimensions it covers (free vs paid, price range, median, link types, by kind, last-check date). This distinguishes it from sibling tools like get_place (single place) and search_places (search), which focus on individual records or discovery rather than catalogue-wide aggregation.

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 conveys that this is the tool for an aggregate, catalogue-wide pricing snapshot, which is distinct from the single-record focus of get_place and the discovery focus of search_places. It does not explicitly state when not to use it or name alternatives, but the context makes the appropriate use case clear enough.

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