generate_image

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

Discloses async nature, cost (credits), default model behavior (omit for default), and reference image constraints (up to 4). No annotations exist, so description carries full burden. No contradictions.

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?

Two sentences pack all essential info: action, async behavior, return type, next steps, cost, model default, and reference image limit. No wasted words.

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?

Covers the full async workflow, credit cost, and reference image usage. No output schema but explains expected response (asset id then PNG URL). Could mention error handling but sufficient for typical use.

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?

Adds meaning beyond schema: explains model usage (omit for default), aspect_ratio examples, and reference_image_urls guide (best with nano-banana). Schema covers 50% of params; description compensates well.

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?

Clearly states 'Generate a 2D image from a text prompt (async)' with specific verb and resource. Distinguishes from sibling tools like animate and 3D generation tools by focusing on 2D image generation.

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?

Provides explicit workflow: returns asset id, then call wait_for_asset or poll get_asset until taskStatus=2, read files.image. Mentions credits, model omission, and reference image guidance. Lacks explicit when-not-to-use but is clear enough.

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