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

Annotations already cover readOnly, idempotent, openWorld, and non-destructive behavior. The description adds valuable non-annotation context: it performs a free registry search then pulls the full billable profile in one call, and it enumerates returned officer/UBO data. Error and rate-limit behavior is not disclosed, but this is strong beyond the 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?

Front-loaded with purpose and return shape, and the example aids invocation. However, the example duplicates examples already present in the input schema, slightly reducing the per-sentence economy.

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?

No output schema exists, so the description appropriately explains return fields including the company profile and officers/UBOs. Safety annotations cover side effects, and the schema fully documents parameters. It omits guidance on multiple matches or the disambiguation workflow, but that is minor.

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?

Schema description coverage is 100%, so the baseline is 3. The description mentions name and country but adds no syntax or format detail beyond what the schema provides for other parameters such as registration_number, kyb_response_id, and company_id.

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?

States a specific verb and resource: KYB verification via the Didit company registry, and lists returned fields including registration number, status, address, officers, and UBOs. It does not explicitly differentiate from siblings such as didit_aml or company_facts, so it falls short of full sibling differentiation.

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?

Implies usage by specifying company name and country as inputs and noting it resolves a free search before pulling a billable profile. There is no explicit when-to-use versus when-not guidance, and siblings such as didit_aml are not contrasted.

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