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

The description goes well beyond the readOnly/openWorld/idempotent annotations: it discloses the GLEIF mapping approach, the ~15 entity cap, the sanctions sources screened, best-effort failure behavior, that only self-reported GLEIF relationships are shown, and that name matches are not proof of identity. No contradiction with 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?

Though long, the description is dense with non-redundant information and every sentence earns its place: purpose, method, scope, failure behavior, return contents, and caveats. The core value proposition is front-loaded in the first sentence.

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?

With no output schema, the description still explains what the tool returns: mapped ownership structure, per-entity CLEAR/HIT results with matched list entry/source/score, and an overall verdict. It also covers edge cases like GLEIF failure and unavailable sanctions binding, making it practically complete for an agent.

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 schema documents both parameters. The description adds meaningful semantics on top: the LEI must be 20 characters, an LEI can be supplied via either field, and the lei parameter overrides a name search. This helps the agent disambiguate parameter usage.

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 states a specific verb and resource: a one-call KYB/AML ownership-chain sanctions screen. It clearly frames the real question being answered and distinguishes itself from a simple top-level-name list check, which separates it from related screening and lookup tools.

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 description explains when this tool is valuable: when ownership-chain exposure must be caught beyond screening only the counterparty name. It references the same matcher as company_trust_check and notes GLEIF-based mapping, giving useful context, though it does not explicitly enumerate sibling alternatives or state hard 'do not use when' conditions.

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