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

Annotations already declare readOnly, idempotent, openWorld and non-destructive, so the bar is lower. The description still adds real value: results carry 'proof of the file it came from' (provenance of the underlying source document) and auth is disclosed ('free tier, or the caller's API key'), which is context annotations cannot express. It omits lookup-failure behavior for an unknown id.

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?

A single sentence, front-loaded with the action and resource, then the parenthetical provenance of the id, then the operational note. Nothing is padded and no clause repeats the tool 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?

For a two-parameter read tool with full schema coverage and safety annotations, the description covers identity, source-of-id, provenance of output and auth tiers - enough to call it correctly. The one gap is that 'proof of the file' is never concretized (what field or document this yields) and there is no output schema to fall back on.

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% - both list (enum of four sources) and id (with pattern and example '36 or RUS0849') are fully documented in the schema. The description adds only the provenance constraint on where ids come from, which is already credited under usage. 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?

States a specific retrieval action ('One current listing'), the resource identity ('by list and id'), and adds the scope qualifier 'current'. It also names the producer tools (sanctions_search, sanctions_list_changes), so an agent can distinguish this from the search and change-feed siblings without opening a 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?

By saying the id is 'as returned by sanctions_search or sanctions_list_changes', it implies the correct workflow order: search/list first, then fetch. It stops short of an explicit exclusion (e.g. what to do when you don't have an id, or that sanctions_search should be used for name lookups), so no full 5.

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