openclaw/docs/tools/image-generation.md

summary, read_when, title

summary	read_when	title
Generate and edit images using configured providers (OpenAI, OpenAI Codex OAuth, Google Gemini, OpenRouter, LiteLLM, fal, MiniMax, ComfyUI, Vydra, xAI)	Generating images via the agent Configuring image generation providers and models Understanding the image_generate tool parameters	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.

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`, set up a provider API key, or sign in with OpenAI Codex OAuth.

Quick start

1. Set an API key for at least one provider (for example OPENAI_API_KEY, GEMINI_API_KEY, or OPENROUTER_API_KEY) or sign in with OpenAI Codex OAuth.
2. Optionally set your preferred model:

{
  agents: {
    defaults: {
      imageGenerationModel: {
        primary: "openai/gpt-image-2",
        // Optional default provider request timeout for image_generate.
        timeoutMs: 180_000,
      },
    },
  },
}

Codex OAuth uses the same openai/gpt-image-2 model ref. When an openai-codex OAuth profile is configured, OpenClaw routes image requests through that same OAuth profile instead of first trying OPENAI_API_KEY. Explicit custom models.providers.openai image config, such as an API key or custom/Azure base URL, opts back into the direct OpenAI Images API route. For OpenAI-compatible LAN endpoints such as LocalAI, keep the custom models.providers.openai.baseUrl and explicitly opt in with browser.ssrfPolicy.dangerouslyAllowPrivateNetwork: true; private/internal image endpoints remain blocked by default.

3. Ask the agent: "Generate an image of a friendly robot mascot."

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

Common routes

Goal	Model ref	Auth
OpenAI image generation with API billing	openai/gpt-image-2	OPENAI_API_KEY
OpenAI image generation with Codex subscription auth	openai/gpt-image-2	OpenAI Codex OAuth
OpenAI transparent-background PNG/WebP	openai/gpt-image-1.5	OPENAI_API_KEY or OpenAI Codex OAuth
OpenRouter image generation	openrouter/google/gemini-3.1-flash-image-preview	OPENROUTER_API_KEY
LiteLLM image generation	litellm/gpt-image-2	LITELLM_API_KEY
Google Gemini image generation	google/gemini-3.1-flash-image-preview	GEMINI_API_KEY or GOOGLE_API_KEY

The same image_generate tool handles text-to-image and reference-image editing. Use image for one reference or images for multiple references. Provider-supported output hints such as quality, outputFormat, and background are forwarded when available and reported as ignored when a provider does not support them. Current bundled transparent-background support is OpenAI-specific; other providers may still preserve PNG alpha if their backend emits it.

Supported providers

Provider	Default model	Edit support	Auth
OpenAI	gpt-image-2	Yes (up to 4 images)	OPENAI_API_KEY or OpenAI Codex OAuth
OpenRouter	google/gemini-3.1-flash-image-preview	Yes (up to 5 input images)	OPENROUTER_API_KEY
LiteLLM	gpt-image-2	Yes (up to 5 input images)	LITELLM_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 or MiniMax OAuth (minimax-portal)
ComfyUI	workflow	Yes (1 image, workflow-configured)	COMFY_API_KEY or COMFY_CLOUD_API_KEY for cloud
Vydra	grok-imagine	No	VYDRA_API_KEY
xAI	grok-imagine-image	Yes (up to 5 images)	XAI_API_KEY

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

/tool image_generate action=list

Tool parameters

Image generation prompt. Required for `action: "generate"`. Use `"list"` to inspect available providers and models at runtime. Provider/model override, e.g. `openai/gpt-image-2`; use `openai/gpt-image-1.5` for transparent OpenAI backgrounds. Single reference image path or URL for edit mode. Multiple reference images for edit mode (up to 5). Size hint: `1024x1024`, `1536x1024`, `1024x1536`, `2048x2048`, `3840x2160`. Aspect ratio: `1:1`, `2:3`, `3:2`, `3:4`, `4:3`, `4:5`, `5:4`, `9:16`, `16:9`, `21:9`. Resolution hint. Quality hint when the provider supports it. Output format hint when the provider supports it. Background hint when the provider supports it. Use `transparent` with `outputFormat: "png"` or `"webp"` for transparency-capable providers. Number of images to generate (1–4). Optional provider request timeout in milliseconds. Output filename hint. OpenAI-only hints: `background`, `moderation`, `outputCompression`, and `user`.

Not all providers support all parameters. When a fallback provider supports a nearby geometry option instead of the exact requested one, OpenClaw remaps to the closest supported size, aspect ratio, or resolution before submission. Unsupported output hints such as quality or outputFormat are dropped for providers that do not declare support and are reported in the tool result.

Tool results report the applied settings. When OpenClaw remaps geometry during provider fallback, the returned size, aspectRatio, and resolution values reflect what was actually sent, and details.normalization captures the requested-to-applied translation.

Configuration

Model selection

{
  agents: {
    defaults: {
      imageGenerationModel: {
        primary: "openai/gpt-image-2",
        timeoutMs: 180_000,
        fallbacks: [
          "openrouter/google/gemini-3.1-flash-image-preview",
          "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 — uses auth-backed provider defaults only:
   • current default provider first
   • remaining registered image-generation providers in provider-id order

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

Notes:

• A per-call model override is exact: OpenClaw tries only that provider/model and does not continue to configured primary/fallback or auto-detected providers.
• Auto-detection is auth-aware. A provider default only enters the candidate list when OpenClaw can actually authenticate that provider.
• Auto-detection is enabled by default. Set agents.defaults.mediaGenerationAutoProviderFallback: false if you want image generation to use only the explicit model, primary, and fallbacks entries.
• Set agents.defaults.imageGenerationModel.timeoutMs for slow image backends. A per-call timeoutMs tool parameter overrides the configured default.
• Use action: "list" to inspect the currently registered providers, their default models, and auth env-var hints.

Image editing

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

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

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

OpenRouter image models

OpenRouter image generation uses the same OPENROUTER_API_KEY and routes through OpenRouter's chat completions image API. Select OpenRouter image models with the openrouter/ prefix:

{
  agents: {
    defaults: {
      imageGenerationModel: {
        primary: "openrouter/google/gemini-3.1-flash-image-preview",
      },
    },
  },
}

OpenClaw forwards prompt, count, reference images, and Gemini-compatible aspectRatio / resolution hints to OpenRouter. Current built-in OpenRouter image model shortcuts include google/gemini-3.1-flash-image-preview, google/gemini-3-pro-image-preview, and openai/gpt-5.4-image-2; use action: "list" to see what your configured plugin exposes.

OpenAI gpt-image-2

OpenAI image generation defaults to openai/gpt-image-2. If an openai-codex OAuth profile is configured, OpenClaw reuses the same OAuth profile used by Codex subscription chat models and sends the image request through the Codex Responses backend. Legacy Codex base URLs such as https://chatgpt.com/backend-api are canonicalized to https://chatgpt.com/backend-api/codex for image requests. It does not silently fall back to OPENAI_API_KEY for that request. To force direct OpenAI Images API routing, configure models.providers.openai explicitly with an API key, custom base URL, or Azure endpoint. The openai/gpt-image-1.5, openai/gpt-image-1, and openai/gpt-image-1-mini models can still be selected explicitly. Use gpt-image-1.5 for transparent-background PNG/WebP output; the current gpt-image-2 API rejects background: "transparent".

gpt-image-2 supports both text-to-image generation and reference-image editing through the same image_generate tool. OpenClaw forwards prompt, count, size, quality, outputFormat, and reference images to OpenAI. OpenAI does not receive aspectRatio or resolution directly; when possible OpenClaw maps those into a supported size, otherwise the tool reports them as ignored overrides.

OpenAI-specific options live under the openai object:

{
  "quality": "low",
  "outputFormat": "jpeg",
  "openai": {
    "background": "opaque",
    "moderation": "low",
    "outputCompression": 60,
    "user": "end-user-42"
  }
}

openai.background accepts transparent, opaque, or auto; transparent outputs require outputFormat png or webp and a transparency-capable OpenAI image model. OpenClaw routes default gpt-image-2 transparent-background requests to gpt-image-1.5. openai.outputCompression applies to JPEG/WebP outputs.

The top-level background hint is provider-neutral and currently maps to the same OpenAI background request field when the OpenAI provider is selected. Providers that do not declare background support return it in ignoredOverrides instead of receiving the unsupported parameter.

When asking an agent for a transparent-background OpenAI image, the expected tool call is:

{
  "model": "openai/gpt-image-1.5",
  "prompt": "A simple red circle sticker on a transparent background",
  "outputFormat": "png",
  "background": "transparent"
}

The explicit openai/gpt-image-1.5 model keeps the request portable across tool summaries and harnesses. If the agent instead uses the default openai/gpt-image-2 with openai.background: "transparent" on the public OpenAI or OpenAI Codex OAuth route, OpenClaw rewrites the provider request to gpt-image-1.5. Azure and custom OpenAI-compatible endpoints keep their configured deployment/model names.

For headless CLI generation, use the equivalent openclaw infer flags:

openclaw infer image generate \
  --model openai/gpt-image-1.5 \
  --output-format png \
  --background transparent \
  --prompt "A simple red circle sticker on a transparent background" \
  --json

The same --output-format and --background flags are available on openclaw infer image edit; --openai-background remains available as an OpenAI-specific alias. Current bundled providers other than OpenAI do not declare explicit background control, so background: "transparent" is reported as ignored for them.

Generate one 4K landscape image:

/tool image_generate action=generate model=openai/gpt-image-2 prompt="A clean editorial poster for OpenClaw image generation" size=3840x2160 count=1

Generate a transparent PNG:

/tool image_generate action=generate model=openai/gpt-image-1.5 prompt="A simple red circle sticker on a transparent background" outputFormat=png background=transparent

Generate two square images:

/tool image_generate action=generate model=openai/gpt-image-2 prompt="Two visual directions for a calm productivity app icon" size=1024x1024 count=2

Edit one local reference image:

/tool image_generate action=generate model=openai/gpt-image-2 prompt="Keep the subject, replace the background with a bright studio setup" image=/path/to/reference.png size=1024x1536

Edit with multiple references:

/tool image_generate action=generate model=openai/gpt-image-2 prompt="Combine the character identity from the first image with the color palette from the second" images='["/path/to/character.png","/path/to/palette.jpg"]' size=1536x1024

To route OpenAI image generation through an Azure OpenAI deployment instead of api.openai.com, see Azure OpenAI endpoints in the OpenAI provider docs.

MiniMax image generation is available through both bundled MiniMax auth paths:

• minimax/image-01 for API-key setups
• minimax-portal/image-01 for OAuth setups

Provider capabilities

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

xAI grok-imagine-image

The bundled xAI provider uses /v1/images/generations for prompt-only requests and /v1/images/edits when image or images is present.

• Models: xai/grok-imagine-image, xai/grok-imagine-image-pro
• Count: up to 4
• References: one image or up to five images
• Aspect ratios: 1:1, 16:9, 9:16, 4:3, 3:4, 2:3, 3:2
• Resolutions: 1K, 2K
• Outputs: returned as OpenClaw-managed image attachments

OpenClaw intentionally does not expose xAI-native quality, mask, user, or extra native-only aspect ratios until those controls exist in the shared cross-provider image_generate contract.

Related

• Tools Overview — all available agent tools
• fal — fal image and video provider setup
• ComfyUI — local ComfyUI and Comfy Cloud workflow setup
• Google (Gemini) — Gemini image provider setup
• MiniMax — MiniMax image provider setup
• OpenAI — OpenAI Images provider setup
• Vydra — Vydra image, video, and speech setup
• xAI — Grok image, video, search, code execution, and TTS setup
• Configuration Reference — imageGenerationModel config
• Models — model configuration and failover