scan_overlay

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

No annotations provided, so the description carries full burden. It mentions a calibration prerequisite, which is valuable, but says nothing about side effects, whether it renders or generates an image, or what happens with invalid scan_id. Behavioral disclosure is thin.

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?

Very short and front-loaded with the main action. The parenthetical calibration note and the region_px comment are packed in, though slightly terse.

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 6-parameter tool with no annotations, no output schema, and 0% schema description coverage, this description is far too sparse. Key parameters and the rendering/output behavior are undocumented.

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 0%, so the description must compensate. It briefly explains region_px ('zooms') and draws attention to calibration, but leaves page, alpha, width_px, drawing, and scan_id entirely unexplained despite 6 parameters.

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?

States a specific verb and resource: draw/overlay a drawing on a scan to check alignment. It's distinguishable from siblings like scan_view or drawing_preview. Slightly informal ('Draw a drawing') but the purpose is clear.

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?

Only hints usage via 'needs calibration', pointing implicitly at scan_calibrate, but gives no explicit when-to-use vs scan_view/scan_preview alternatives. An agent could confuse this with other scan rendering tools.

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