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

No annotations are present, so the description carries the full disclosure burden. It states the source is preserved, a derivative is stored under a one-hour file_reference, dual hashes are returned, and it explicitly lists excluded side effects such as payment and external contact.

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 a single dense paragraph of five sentences, each adding distinct information: core purpose, anti-heuristic rule, required evidence, resulting artifacts, and excluded actions. No sentence is wasted, though it could be tightened slightly.

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 tool with 6 required params, nested validation and evidence objects, and no annotations, the description covers the essential call context: required evidence, enforced checks, artifacts produced, and absent side effects. The output schema adequately covers return values.

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?

With only 17% schema coverage, the description compensates by explaining the role of source_sha256, unit_evidence (system, revision, operation), and validation (expected envelope). It also clarifies the fixed m→mm conversion context. The file_reference parameter is not explained, but its schema fully self-documents.

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 names a specific verb and resource: create a millimetre-scaled derivative from an STL. It explicitly scopes to unit normalization and rules out downstream actions ('no supplier selection...'), which distinguishes it from sibling tools.

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?

It states clear prerequisites (exact SHA-256, exporter statement, expected-envelope check) and a behavioral rule ('never guesses units'). This implies when the tool should be used, but it does not explicitly name alternatives or say when not to use it.

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