draw_line

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

With no annotations, the description carries the full burden and discloses the key behavioral trait that the line is L-shaped (horizontal first, then vertical). This goes beyond the parameter names and provides meaningful context. It doesn't mention potential side effects like canvas overwriting, but the core drawing behavior is well described.

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, short, front-loaded sentence in Chinese (14 characters) with no filler words. It efficiently conveys the verb, resource, and key behavioral detail.

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 simple drawing tool with four integer parameters and no output schema, the description is nearly complete. It specifies the drawing behavior and the pair of points. Missing details like coordinate origin or start/end order are not critical to correct invocation, and the description is adequate for a low-complexity tool.

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 0%, so the description compensates by explaining that coordinates represent two points between which the line is drawn. The parameter names x1,y1,x2,y2 are self-explanatory, and the description adds the L-shaped path meaning. It lacks explicit details on coordinate units or order, but is sufficient for basic invocation.

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 it draws a polyline between two points with a specific orthogonal path (horizontal then vertical). This is a specific verb+resource combination that distinguishes it from siblings like draw_box and draw_arrow.

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 implies usage for creating orthogonal polylines on the canvas but does not explicitly state when to prefer this over alternatives. The path specification gives some selection context, but there are no clear exclusions or references to sibling tools.

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