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

The description meaningfully extends the readOnly/idempotent annotations by disclosing the paginated return shape, the specific fields returned (source_class, provenance, snapshot, pagination, limits), empty-data behavior on no match, and argument-error behavior on invalid input. This is substantial behavioral context beyond 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 compact and front-loads the purpose before returning to inputs, outputs, and edge cases. Minor redundancy exists in 'Inputs: standard_number' and 'Required: standard_number', but the overall structure is efficient and each major concern is addressed in a separate clause.

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?

Even without an output schema, the description conveys the essential return structure, pagination behavior, no-match behavior, required input, and error condition. Given the tool's simple parameter set and rich annotations, an agent has enough information to invoke it correctly and interpret results.

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 100%, so the schema already documents all four parameters in detail. The description only mentions standard_number and its required status, adding little beyond what the schema already states. This fits the baseline of 3 where the schema carries the semantic weight.

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?

Description opens with a specific verb and resource: 'Find occurrences of a recorded standard number in CCC reference metadata.' This clearly distinguishes it from sibling tools focused on products, standards metadata, or recalls. The added qualifier 'Reference occurrences only; does not imply equivalence or applicability' further sharpens the tool's scope.

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 gives clear context on when to use the tool: to find recorded standard-number occurrences in CCC reference metadata. It also provides an implicit exclusion by warning that results do not imply equivalence or applicability. It does not name alternative sibling tools, but the boundaries are clear enough for an agent to route correctly.

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