draw_image_to_file

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

With no annotations, the description carries the full burden and does so thoroughly. It discloses that parent directories are not created, invalid commands are skipped with warnings, no-valid-command fails, later commands overpaint earlier ones, drawing outside the canvas is clipped, and colors follow specific formats.

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 long, but the length is justified by the tool's complexity and the absence of schema-level documentation. It is front-loaded with a one-sentence purpose, then organized into clear labeled sections with a concrete example.

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 tool with four required parameters, a free-form commands array, and no annotations, the description covers nearly every decision an agent needs to make: file path rules, canvas size, command shapes, validation behavior, coordinate system, painting order, and colors. The presence of an output schema means return-value details are not required.

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 input schema provides only names and basic types, so schema coverage is effectively 0%. The description compensates completely by explaining output_path semantics, width/height meaning, command structure, all supported shape fields, defaults, and coordinate/color conventions.

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 opens with a specific verb-resource pair: it draws a picture and saves it to a file. It also distinguishes itself from the sibling draw_image by emphasizing file output, so an agent can tell the tools apart.

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 saving-to-file behavior implies when this tool is appropriate, but the description never explicitly states when to use it versus draw_image or what conditions would favor one over the other. This is usable but implied rather than explicit.

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