extract_drawing_dimensions

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It openly states what the tool returns, that it relies on OCR, and its known failure mode ('Ø often misreads as ‘9’'), and even instructs how to mitigate that limitation. This is unusually transparent.

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, front-loaded with the core behavior, and every sentence adds value: the output shape, the pixel-position mapping, the usage priority, and the known OCR limitation. The all-caps precaution is effective without bloating the text.

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 tells the agent what the result will contain (grouped callouts with pixel positions) and how to use it (map to features, cross-check important dimensions). For a one-parameter read tool, this fully covers selection and invocation needs.

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% and the sole parameter imagePath is already documented as a filesystem path to a drawing PNG. The description restates 'PNG' but adds no new detail about path format, supported file types, or coordinate conventions. Baseline 3 is appropriate since the schema does the heavy lifting.

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 ('OCR'), a resource ('drawing PNG'), and the exact output ('numeric callouts grouped by kind: length / radius / diameter / thread / angle / count / scale'). It also clarifies that callouts include pixel positions, making it easy to distinguish from sibling image tools like crop_image or render_*.

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 explicitly tells the agent when to use this tool ('USE THIS BEFORE READING DIMS BY EYE') and why (Tesseract is more reliable than a vision pass on small text). It also names an alternative for follow-up verification ('cross-check high-significance dims with crop_image at native resolution').

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