Image Generation

Image Generation

The image_generate tool lets the agent create and edit images using your configured providers. Generated images are delivered automatically as media attachments in the agent’s reply.

Note

The tool only appears when at least one image generation provider is available. If you don’t see image_generate in your agent’s tools, configure agents.defaults.imageGenerationModel or set up a provider API key.

Quick start

1. Set an API key for at least one provider (for example OPENAI_API_KEY or GEMINI_API_KEY).
2. Optionally set your preferred model:

{
  agents: {
    defaults: {
      imageGenerationModel: "openai/gpt-image-1",
    },
  },
}

3. Ask the agent: “Generate an image of a friendly lobster mascot.”

The agent calls image_generate automatically. No tool allow-listing needed — it’s enabled by default when a provider is available.

Supported providers

Provider	Default model	Edit support	API key
OpenAI	gpt-image-1	Yes (up to 5 images)	OPENAI_API_KEY
Google	gemini-3.1-flash-image-preview	Yes	GEMINI_API_KEY or GOOGLE_API_KEY
fal	fal-ai/flux/dev	Yes	FAL_KEY
MiniMax	image-01	Yes (subject reference)	MINIMAX_API_KEY

Use action: "list" to inspect available providers and models at runtime:

/tool image_generate action=list

Tool parameters

Parameter	Type	Description
prompt	string	Image generation prompt (required for action: "generate")
action	string	"generate" (default) or "list" to inspect providers
model	string	Provider/model override, e.g. openai/gpt-image-1
image	string	Single reference image path or URL for edit mode
images	string[]	Multiple reference images for edit mode (up to 5)
size	string	Size hint: 1024x1024, 1536x1024, 1024x1536, 1024x1792, 1792x1024
aspectRatio	string	Aspect ratio: 1:1, 2:3, 3:2, 3:4, 4:3, 4:5, 5:4, 9:16, 16:9, 21:9
resolution	string	Resolution hint: 1K, 2K, or 4K
count	number	Number of images to generate (1–4)
filename	string	Output filename hint

Not all providers support all parameters. The tool passes what each provider supports and ignores the rest.

Configuration

Model selection

{
  agents: {
    defaults: {
      // String form: primary model only
      imageGenerationModel: "google/gemini-3-pro-image-preview",

      // Object form: primary + ordered fallbacks
      imageGenerationModel: {
        primary: "openai/gpt-image-1",
        fallbacks: ["google/gemini-3.1-flash-image-preview", "fal/fal-ai/flux/dev"],
      },
    },
  },
}

Provider selection order

When generating an image, OpenClaw tries providers in this order:

1. model parameter from the tool call (if the agent specifies one)
2. imageGenerationModel.primary from config
3. imageGenerationModel.fallbacks in order
4. Auto-detection — queries all registered providers for defaults, preferring: configured primary provider, then OpenAI, then Google, then others

If a provider fails (auth error, rate limit, etc.), the next candidate is tried automatically. If all fail, the error includes details from each attempt.

Image editing

OpenAI, Google, fal, and MiniMax support editing reference images. Pass a reference image path or URL:

"Generate a watercolor version of this photo" + image: "/path/to/photo.jpg"

OpenAI and Google support up to 5 reference images via the images parameter. fal and MiniMax support 1.

Provider capabilities

Capability	OpenAI	Google	fal	MiniMax
Generate	Yes (up to 4)	Yes (up to 4)	Yes (up to 4)	Yes (up to 9)
Edit/reference	Yes (up to 5 images)	Yes (up to 5 images)	Yes (1 image)	Yes (1 image, subject ref)
Size control	Yes	Yes	Yes	No
Aspect ratio	No	Yes	Yes (generate only)	Yes
Resolution (1K/2K/4K)	No	Yes	Yes	No

Related

• Tools Overview — all available agent tools
• Configuration Reference — imageGenerationModel config
• Models — model configuration and failover