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

The description goes well beyond the readOnlyHint and openWorldHint annotations by disclosing the ranking methodology, the approximately 10% weight on settlement traction, the ranking_version field, and the need_blind_ranking behavior. It also explicitly warns about a 'units map' containing scoring caveats, such as compliance caps and the $10 volume floor, which is valuable behavioral context an agent would otherwise not know.

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 long but highly information-dense. It front-loads the primary purpose and invocation, then explains the ranking logic and response caveats in structured sentences. Every sentence earns its place; it is not bloated, though it could be tightened slightly by separating the caveat list into a clearer structure.

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 read-only ranking tool with no output schema, the description is remarkably complete: it explains when to use it, what parameters to pass, what the response contains (ranked recommendations, ranking_version, need_blind_ranking, units map), and how the ranking works. It also includes important caveats and a pointer to read units before comparing scores, leaving little ambiguity for an agent deciding whether and how to call it.

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 already documents all 8 parameters with 100% coverage, so the baseline is 3. The description adds a small amount of extra meaning by explaining q as 'a need in words' and grouping the relevant filter parameters, but it does not provide new details beyond what the schema descriptions already contain.

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 that the tool converts a natural-language need (q) into a single recommended service, returning up to 20 ranked recommendations. It distinguishes itself from list-returning tools by explicitly framing it as 'the free ranking step between searching and paying' rather than a list to read.

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?

It gives a clear when-to-use condition: call when you want one service to call rather than a list to read, and positions it between searching and paying. It does not explicitly name the sibling alternatives, but the 'rather than a list to read' phrase effectively tells the agent when not to use this tool in favor of a list-returning one.

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