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

Beyond the readOnlyHint/idempotentHint annotations, the description discloses two distinct output modes (summaries without arguments vs full case file with per-quarter table) and a provenance guarantee that figures are audited against primary filings. This adds meaningful behavioral context without contradicting 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?

The description is compact and front-loaded, with no redundant sentences. The opening verb and resource are immediate, and all subsequent details (case list, audit, argument behavior, cohort caveat) serve a purpose.

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 single-parameter read-only tool with no output schema, the description thoroughly covers both the default return (all seven verdict summaries) and the single-file return (per-quarter table). The cohort caveat prevents misuse, and no prerequisites or edge cases are left unaddressed.

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 fully documents the optional slug parameter, but the description adds the seven valid case names as implicit slug values, making parameter selection easier. Since no enums exist, this compensation is valuable and goes beyond the schema's example.

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 opens with the verb 'Read' and identifies the exact resource: seven European case files, listing each by name and outcome category (failed, stressed survivors, control). This clearly differentiates it from sibling tools like evidence_us and evidence_india.

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 implies use for European case evidence and explicitly warns not to treat it as a cohort or quote a European recall percentage, providing a clear when-not. However, it does not name alternative tools explicitly, so it stops short of fully satisfying the 'alternatives' criterion.

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