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

Annotations already declare readOnlyHint=true, openWorldHint=false, idempotentHint=true, destructiveHint=false, so the safety profile is fully covered. The description adds valuable behavioral context: it separates blocking vs non-blocking gaps, and explicitly states it is a checklist over supplied fields, reading no documents and judging no evidence. This goes beyond the annotations.

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, each earning its place. The first states the core function and legal basis, the second describes the output and its blocking/non-blocking distinction, and the third sets expectations about scope. No fluff, no repetition of schema details.

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?

The tool has a rich input schema (15 properties) and an output schema, but the description is still complete enough for an agent to decide whether to call it. It explains the legal basis, the output format, and the scope limitation. It doesn't explain the exact mapping of Article 9 items to schema fields, but that is likely in the output schema or the tool's internal logic. Given the annotations cover safety and the description covers purpose and scope, a 4 is appropriate.

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%, so the description must compensate. The description explains the purpose of the 'suppliers' parameter implicitly: it is the set of fields to check against Article 9. It also clarifies that the tool operates on the supplied fields, not on external documents. However, it does not enumerate the specific fields or explain how the checklist maps to the schema properties, so it doesn't fully compensate for the 0% coverage.

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 states a specific verb ('Check'), a precise resource (each supplier's file against Article 9(1) of Regulation (EU) 2023/1115), and the exact output (unmet items with article reference and what to request). It also distinguishes itself from siblings by clarifying it is a checklist over supplied fields, not a document reader or evidence judge.

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?

The description clearly states when to use it: to find missing Article 9 information per supplier before filing. It also gives an exclusion: 'it reads no documents and judges no evidence,' which implies it should not be used for document analysis or evidence quality assessment. It does not explicitly name alternative sibling tools, but the context is clear enough.

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