pixel_draw_line

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

Annotations indicate destructiveHint=true. The description adds useful behavioral details: endpoints may lie outside canvas, 'transparent' erases, and return value includes a rendered image when preview=true. These go beyond 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?

The description is three sentences: purpose, edge case/behavior, and return value. No wasted words, front-loaded with the core action.

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?

No output schema exists, but the description explains the return format (JSON with canvas, line, color, plus image on preview) and failure case. It covers the endpoint clipping behavior. Lacks details about modification semantics (e.g., does it update the file?), but overall adequate.

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 property descriptions exist (e.g., 'Start X'), but overall schema description coverage is 0%. The description adds meaning: endpoints can be outside, transparent erases, and preview returns image. It does not cover thickness or path explicitly, but provides key context.

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 explicitly states 'Draw a straight line between two points on a canvas,' which is a specific verb+resource. It distinguishes from siblings like pixel_draw_rect and pixel_draw_ellipse by focusing on lines.

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?

The description does not explicitly state when to use this tool versus alternatives. Usage is implied by the tool's purpose, but no when-not-to-use or alternative comparisons are provided.

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