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

The annotations already cover the safety profile (readOnly, idempotent, non-destructive, closed-world), so the free credit is lower, yet the description still adds real behavioral context absent from structured fields: the fresh/stale snapshot semantics and the empty-state signal (snapshot.retrieved false when no snapshot exists). What it omits is matching semantics (exact vs. fuzzy/substring) and result-set/pagination behavior, which matter for interpreting hits and misses.

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 with no filler, front-loaded with purpose before the return-shape detail, which is justified given there is no output schema. The second sentence is long and clause-stacked (stale flag plus snapshot.retrieved semantics), which slightly hurts scanability.

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 carries the return-value burden by naming the fields returned and the two freshness flags, including the empty-snapshot case. Gaps remain around match behavior (exact ID vs. partial name), limiting/truncation of results, and jurisdictional boundaries relative to sibling sanction lists.

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 75%, with query, record_type, and un_list_type already documented in the schema, so the baseline is a 3. The description confirms aliases and the un_list_type regime field, but adds no syntax, format, or example guidance beyond the schema, and the undocumented limit parameter is not addressed at all.

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) and a precisely named resource (the UN Security Council Consolidated Sanctions List, individuals and entities), with the matching keys (name or alias) named in the same sentence. An agent can immediately distinguish this from the EU, OFAC, and UK sibling search tools by the jurisdiction-scoped list name alone.

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: an agent infers 'use this when you need the UN list' from the resource name, but the description never states when to prefer it over eu_sanctions__search, ofac_sanctions__search, or uk_sanctions__search, nor any exclusion such as 'does not cover national or EU designations. A single routing sentence would raise this considerably.

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