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

Annotations already declare readOnly, idempotent, non-destructive and open-world behavior, so the bar is lower. The description adds real value by disclosing the data-freshness model: results come from filtering a cached snapshot by listedOn rather than a live upstream delta feed, which affects how stale results may be.

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, zero padding. The primary behavior is front-loaded and the mechanism note follows as supporting context.

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 still conveys what is returned (added/updated entities) and the underlying mechanism. Minor gaps remain around pagination/limit defaults and return shape, but nothing critical for correct invocation is missing.

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%; 'since' and 'limit' are documented in the schema, while the 'source' enum has no description. The description compensates by clarifying that 'since' is an ISO date and, crucially, that the delta is computed against the listedOn field, which the schema never states.

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 gives a specific verb and resource: return entities added or updated since an ISO date for a chosen source list. The 'delta feed' framing implicitly separates it from the sibling screen/search tools (sanctions_screen_entity, sanctions_search_alias), but no sibling is named explicitly.

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 implied by the delta semantics, and the rationale ('the four official lists do not all expose a public delta feed') explains why the tool exists. However, it never states when to prefer this over sanctions_status_summary or a full snapshot pull, and gives no exclusions.

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