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

Annotations already cover safety (readOnly, idempotent, non-destructive, closed-world), so the description's added value is the coverage caveat and the meaning of the return value ('hit=true for a local match'). The false-negative warning is high-value disclosure. It stops short of describing the full response shape or how multiple alias matches are represented.

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?

Three short sentences, zero filler, with the scope constraint front-loaded and the critical caveat attached directly to the return-value claim.

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 screening call with no output schema, the description supplies the essential context: data source, matching behavior, hit semantics, and the coverage limitation. It only marginally under-specifies the response beyond hit=true, which is acceptable given the tool's simplicity.

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 coverage is 100%, so the baseline is 3; the description earns above baseline by specifying case-insensitivity, substring (not exact) matching, and that indexed aliases are searched — semantics the schema's one-line description does not convey.

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 (Search) against a precisely bounded resource (MORVS's partial local OFAC SDN index), including match semantics (case-insensitive substring, indexed aliases). The qualifiers 'partial' and 'local' implicitly separate it from broader screening siblings such as screen_all, screen_batch, watchlist and debarments_check, so an agent can route correctly without opening the schema.

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?

Explicitly frames the negative case: 'A non-match is not sanctions clearance', and directs the agent to /coverage and OFAC's current official lists for verification. That is clear when-to-trust and when-to-escalate guidance, though it never names an alternative sibling tool for broader coverage.

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