set_page_background

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

With no annotations, the description must fully convey behavioral traits. It states that a rectangle is created and a color is applied, but it omits details such as whether the rectangle is placed on the current layer, if it replaces any existing background, or what happens if the document lacks the specified color swatch. These gaps reduce transparency.

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 sentence with no extraneous words. It is appropriately concise for the action described, though it could benefit from slightly more detail without becoming verbose.

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 has 3 parameters and no output schema, the description is moderately complete. It explains the overall effect but does not cover edge cases or the exact outcome (e.g., that a new page item is created). For a straightforward operation, it is adequate but not thorough.

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 coverage is 100%, so the baseline is 3. The description does not add meaningful information beyond what the schema already provides for the parameters. It mentions 'specified color' but that is already clear from the schema description. No additional context about valid values or interactions is given.

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 verb 'set' and the resource 'page background', and explicitly mentions the method of creating a full-page rectangle with a specified color. This distinguishes it from sibling tools like 'apply_color' or 'create_rectangle' by combining them into a single step.

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?

No explicit guidance is given on when to use this tool versus alternatives. For instance, it does not explain that it creates a new rectangle object each time, potentially overlapping previous backgrounds, nor does it mention the prerequisite that the color must be a swatch already existing in the document. This lack of context leaves the agent uncertain about preconditions and side effects.

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