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

Annotations already indicate readOnly and non-destructive, but the description adds significant behavioral context: it states the result explicitly sets supplierDeclared=true and independentlyVerifiedByJithox=false, clarifies that nothing is independently verified, and explains that answers come from either the live EPREL API or a synthetic fixture with provenance.sourceAuthority identifying the source. It also warns that this is preflight evidence only, not a conformity determination. No contradiction with 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?

The description is composed of three dense but purposeful sentences. It front-loads the core purpose and then adds essential caveats about verification, source, and legal limitations. No redundant or filler content exists.

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?

Given only one parameter with full schema coverage, an output schema, and rich annotations, the description covers the essential context: purpose, source mode (live vs. synthetic), verification status, and preflight-only limitations. It does not explain error handling, but that is not necessary given the output schema and annotations.

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?

The input schema provides a complete description of publicRecordId ('The public record identifier whose declared label data to return') with 100% coverage. The description adds no additional parameter-level meaning, so a baseline of 3 is appropriate since the schema already handles parameter semantics.

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 uses a specific verb 'Structure' and names the resource as 'supplier-DECLARED energy-label / product-sheet data for one public record', which clearly differentiates from sibling tools like search_eprel_products or compare_eprel_product_metrics. It also explicitly contrasts declared vs. independently verified data, further defining the tool's purpose.

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 states this is for one public record and explicitly excludes conformity, CE, GPSR, safety, or market-access determinations, giving clear when-not-to-use context. However, it does not name alternative sibling tools (e.g., get_eprel_product_record) for different needs, so it lacks explicit alternative guidance.

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