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

Annotations already declare readOnlyHint=true, and the description redundantly confirms 'read-only'. It adds some context by noting that results/status are returned and by giving the API endpoint GET /checks?applicant_id=…, but says nothing about pagination, ordering, or response shape. With annotations covering safety, this is a modest addition.

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?

One compact sentence plus the API endpoint, with the core purpose front-loaded. Every element earns its place and there is no filler.

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 list tool with full schema coverage and safety annotations, the description covers purpose, scope, and the API path. It does not mention pagination or return-shape details, but no output schema exists and the gap is minor for this operation.

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 documents the single applicant_id parameter with 100% description coverage, and the description only implies it through 'for an applicant'. No additional format or constraint detail is provided, so the schema does the heavy lifting.

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 gives a specific verb (list) and resource (verification checks) scoped to an applicant, and the plural 'checks' implicitly separates it from the singular get_check sibling. However, it never explicitly names or contrasts with any sibling, so it falls short of the top score.

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 states what the tool does but offers no when-to-use guidance, no prerequisites, and no mention of alternatives such as onfido_get_check for a single check. The agent must infer all usage conditions.

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