GD&T: Feature Control Frame (ISO 1101)

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

Annotations only mark destructiveHint=false, so the description carries the behavioral burden. It adds two non-obvious behaviors: identical output across COM and ezdxf, and recording of referenced datums so that critique can match them against datum features. 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?

Two sentences, with the core action front-loaded and each additional sentence providing non-obvious information. No filler or repeated schema content.

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?

Together with a 100% documented schema and an output schema, the description is execution-ready: it states what the tool draws, its cross-backend guarantee, and how datums affect downstream critique. No critical invocation details are 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 100%, so the baseline is 3. The description adds one meaningful semantic by explaining that provided datums are recorded for critique validation, but it does not enrich the other parameters beyond what the schema already 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 first sentence names a specific verb ('Draw'), a standard ('ISO 1101'), and a distinct object ('feature control frame'), with an implementation clue ('from LINE + TEXT primitives'). That separates it from entity-creation and drawing-CAD siblings even without naming an alternative.

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?

No explicit when-to-use or when-not-to-use guidance is given. The description implies the use case through 'Draw an ISO 1101 feature control frame' and the note about recorded datums for critique, but an agent must infer the boundary with related tools like datum_feature.

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