line

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

No annotations are provided, so the description carries the full burden. It discloses the algorithm but does not mention side effects (e.g., whether drawing overwrites existing pixels), return value, prerequisites like canvas existence, or any error behavior. The lack of such detail is a gap for a mutation tool.

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 a single, front-loaded sentence that immediately states the core action and target. No unnecessary words or repetition, making it highly concise and well-structured.

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?

Given the tool's simplicity and full schema coverage, the description is minimally adequate. However, with no annotations or output schema, it lacks context about side effects and integration with sibling tools. It covers the essential purpose but not the broader operational context.

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?

The schema has 100% coverage with descriptive parameter names (Start X, End X, etc.), so the baseline is 3. The description adds no new semantic meaning to the parameters beyond what the schema already provides, though it does tie x1/y1 and x2/y2 to the line endpoints.

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 clearly states the tool's purpose: drawing a line between two points on a canvas. It uses a specific verb ('Draw'), names the resource ('canvas'), and distinguishes itself from siblings like pixel, rect, or fill. Mentioning Bresenham's algorithm adds further specificity.

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 implies usage for drawing lines but provides no explicit guidance on when to use this tool versus alternatives like pixel or rect. No when-not-to-use cases or alternative tool names are mentioned, leaving the context implicit.

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