design_trace_lines

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

No annotations are supplied, so the description carries the full burden. It usefully discloses the internal pipeline (edge detection runs first, then line finding), but says nothing about whether the tool mutates the document, whether a trace layer is written (visible only via the createLayer param), or what is returned.

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 short sentences, front-loaded with what the tool does, followed by the one implementation detail that matters for interpreting the result. Nothing is wasted.

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 5-parameter tool with no annotations and no output schema, the description covers the conceptual behavior but leaves the mutation/return story unclear — an agent cannot tell whether lines are returned as data, drawn to the canvas, or placed on a new layer without reading the schema. The description should close that gap.

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 threshold, minLineLength, maxLineGap, sourceId and createLayer are all already documented. The mention of Hough voting indirectly explains what threshold means, but adds no format, range, or default guidance beyond the schema — the baseline 3 applies.

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?

Names a specific verb (detect) and resource (straight line segments) and even names the algorithm (Hough transform), which cleanly separates it from design_trace_contours, design_trace_edges, and design_trace_splines. It does not explicitly contrast itself with those siblings, so it stops short of a 5.

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?

"Detect straight line segments" implies the use case (vectorizing linear features from a raster source), but there is no explicit when-to-use, when-not-to-use, or pointer to design_trace_shapes/design_add_line for non-straight geometry. The agent has to infer selection criteria from the resource name alone.

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