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

Annotations already declare read-only/idempotent/non-destructive, but the description adds substantial behavioral context beyond them: it will never fabricate a match or a clear result, it exposes lists_screened for verification, and it defines the partial_screening failure mode. The explicit exclusion of the UN list for licensing reasons is exactly the kind of coverage caveat annotations cannot convey.

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 the core action and target lists, then caveats, then a compact cost/key tag. Dense and effective, though the heavy capitalization and multi-clause sentences make it slightly harder to scan than it needs to be.

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 compensates by naming key return signals (lists_screened, reason_code values) and the partial-result contract. It does not fully describe the shape of a hit record, but the critical interpretation guidance an agent needs is present.

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 name/type/country are already documented with examples and enum values. The description adds only the script hint (Latin or Arabic), which is largely mirrored in the schema, so the baseline 3 applies.

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 (screen) and resource (name/entity) and enumerates the exact lists consulted (OFAC SDN, EU consolidated, UK Sanctions List). It also carves out scope precisely by naming what is NOT covered (UN Consolidated List), so an agent can distinguish it from siblings like check_compliance or verify_company_record.

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?

Gives clear context for when the tool applies (screening a name/entity, Latin or Arabic script) and useful operating guidance about checking lists_screened and treating reason_code 'partial_screening' as non-clear. It does not, however, name an alternative sibling tool or state when to prefer a different screening/compliance tool, so it stops short of full routing guidance.

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