Expand a creation into a wallpaper

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

The description discloses critical behavioral traits beyond the annotations: it spends the account's credit, the price varies by dimension, quality is fixed at Ultra, unknown dimension values are rejected, and the wait/queue behavior is explained. This goes beyond the simple hints and gives the agent a clear picture of side effects and return behavior.

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 compact and front-loaded with the main purpose. Each sentence adds value: purpose, cost, dimensions, optional steering, and return behavior. No fluff or repetition.

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 6 parameters, no output schema, and 21 siblings, this description is sufficiently complete. It explains what the tool does, how the output is returned (finished creation or queueId), the pricing model, and the available dimensions. An agent can confidently invoke this tool without further clarification.

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?

While the schema has 100% coverage for parameter descriptions, the description adds meaningful semantic context: it links dimension to price, explains that refs and prompt steer the newly painted areas, and clarifies the wait budget behavior for the wait parameter. This enriches the parameter understanding beyond the schema.

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 function: expanding an existing creation into a wallpaper format. It uses a specific verb ('expand') and resource ('creation'), and differentiates itself from sibling tools like generate_image or generate_with_refs by focusing on wallpaper expansion with preserved content and outward painting.

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 when to use this tool (for expanding an existing creation into a wallpaper) and provides context about pricing, fixed quality, and available dimensions. It does not explicitly exclude alternatives, but the scenario is clear enough for an agent to decide. It could have explicitly contrasted with generate_similar or generate_with_refs, but the core usage is well conveyed.

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