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

With annotations already covering safety (readOnly, idempotent, non-destructive, closed-world), the description goes well beyond them: it discloses that DOB, identity documents, and contact details are dropped at ingest, states the cost (1 credit/call with a key) and the unauthenticated cap (5-row preview, 20 calls/day). These are exactly the operational constraints an agent needs before invoking.

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 sentences, front-loaded with what the corpus contains, then data-handling caveat, then cost/limit. Dense without waste, though the em-dash clause 'with regimes, aliases, and dates' is slightly unpacked relative to its value.

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 13-parameter, no-output-schema tool, the description compensates well on the result side: it describes record contents (regimes, aliases, dates) and what is redacted (PII), plus cost and preview limits. The main gap is filter semantics for the many query parameters, which are neither in the schema nor the description.

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 0% across 13 parameters, so the description carries the full semantic burden but only clarifies 'q' (searches all text fields) and the AND-combination rule. Key filters — name (exact vs. partial match), regime, countries, designation_type, designation_source, unique_id, and the four date bounds — are left undocumented in both schema and description.

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 names a specific resource and scope: 'Every designation on the official UK Sanctions List (FCDO) — individuals, entities, and ships.' The dataset ('UK Sanctions List') is distinct enough from the query_uk_* siblings and query_eu_ted that an agent can tell it apart, but the verb is implicit (retrieval/search) rather than stated, and no sibling is named to confirm the boundary.

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?

'Normalized for supplier due diligence' implies a use case, and 'Filters combine with AND; q searches all text fields' gives operational guidance for combining filters. However, there is no explicit when-to-use/when-not guidance and no routing to or away from alternative tools (e.g., query_eu_ted, query_sam_exclusions), so usage must be inferred.

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