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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is known. The description adds useful behavioral context: 'Keyless sources only' indicates no API keys are needed, 'combined into one row per company' clarifies aggregation behavior, and 'documented risk score' hints at how results are presented. It does not contradict annotations, and the extra details go beyond annotation coverage.

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 core description is one dense sentence that front-loads the tool's purpose and components, followed by a brief pricing note. Every word contributes meaningful information with no fluff or repetition of schema details.

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 four well-documented parameters and no output schema, the description covers the essential behavior: the composite nature of the rollup, the per-company row output, and the risk score. It could be more explicit about what the 'documented risk score' contains or how the row is structured, but for the tool's complexity, it is sufficiently 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 schema already provides 100% coverage with rich descriptions for all four parameters, including defaults, allowed values, and per-parameter cost implications. The tool description itself does not add new parameter-level insights beyond referencing the checks, so the baseline score of 3 is appropriate.

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 uses a specific verb 'Screen' and resource 'counterparty', clearly listing all four data sources (OFAC/EU sanctions, GLEIF registry, litigation history, hiring signal) and the output format ('one row per company with a documented risk score'). This distinguishes it from sibling tools like sanctions-screening or litigation-check, which are single-purpose.

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 phrase 'Screen a counterparty in one call' implies this is the comprehensive, combined alternative to individual checks, giving clear context for when to use it. However, it does not explicitly state scenarios where a specialized sibling tool would be preferred, so the guidance is clear but not exhaustive.

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