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

Annotations already declare readOnly, idempotent, non-destructive and closed-world, so the safety profile is covered. The description earns credit by disclosing behavior annotations cannot express: results come from a local snapshot, a `stale` flag indicates the snapshot passed its freshness window, and `retrieved: false` means no snapshot has ever been fetched — a real operational caveat. It stops short of saying what happens on a stale/absent snapshot (error vs empty result).

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?

Two sentences, front-loaded with what is searched and what comes back, then the snapshot-freshness caveat. Every clause carries information an agent would otherwise have to guess; nothing is redundant with the name or title.

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 correctly takes on the burden of describing the return shape (aliases, regime, DOB, nationality, measures) and the stale/retrieved flags, which is what an agent needs to interpret results. It omits result-set granularity (pagination vs the `limit` cap) and behavior when no snapshot exists, so it is strong but not exhaustive.

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 67%: `query` ("Name, alias or exact ID number") and `regime` are already documented in the schema, and `limit` is self-explanatory with a default of 10 and max of 100. The description restates name/alias matching but adds nothing on match semantics (exact vs fuzzy/prefix), on what `regime` values are valid, or on the exact-ID path the schema mentions. Baseline 3 is appropriate.

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 uses a specific verb ("Search") and a precisely scoped resource ("the UK Sanctions List (HM Treasury / FCDO consolidated financial sanctions designations)"), which lets an agent separate it from the eu_sanctions, ofac_sanctions and un_sanctions siblings by jurisdiction. It never names those siblings or states the routing rule explicitly, which keeps it just short of a 5.

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?

Usage is only implied: the tool searches "by name or alias", so an agent can infer it is the name-lookup entry point, but there is no explicit when-to-use statement, no note on when to prefer eu/ofac/un sanctions tools, and no guidance on prerequisites or snapshot availability.

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