Pixara MCP Server

An MCP server that gives LLMs direct access to OpenRouter's Image API to generate images, edit/transform existing ones, and browse the model catalog, all through 4 tools.

I built this because I saw that OpenRouter announced a new Image API (/api/v1/images) that gives you one endpoint to use image generation and image editing models like GPT Image, Nano Banana, Flux, Recraft, and more. Use the pixara_list_image_models tool to see the full, current models list from OpenRouter.

Features

Generate images from a text prompt against any OpenRouter image model
Edit/transform images (img2img) using a local file, a URL, or raw base64 as the reference, and the tool reads and encodes local files for you
List models with filtering by provider, name, and capability (img2img, streaming, transparent background), plus pagination
Inspect a model's endpoint details: per-provider pricing, supported parameters, and allowed passthrough options — before you spend a call on something it doesn't support
Generated images are decoded and saved to disk, so responses stay small and a file path is returned
Clear error messages for common failure modes: bad/conflicting params, invalid key, insufficient credits, rate limits, provider unavailable

Quick start (recommended)

Pixara is published on npm as @pinkpixel/pixara-mcp.The easiest way to use it is via npx — no install, no cloning, no build step.

Add this to your MCP config (claude_desktop_config.json) for Claude Desktop, or your MCP client's .json config file:

{
  "mcpServers": {
    "pixara": {
      "command": "npx",
      "args": ["-y", "@pinkpixel/pixara-mcp"],
      "env": {
        "OPENROUTER_API_KEY": "sk-or-v1-your-key-here",
        "OPENROUTER_IMAGE_OUTPUT_DIR": "/absolute/path/to/wherever/you/want/images"
      }
    }
  }
}

Restart the client and you should see the four pixara_* tools available. npx -y fetchesand caches the package on first run, so there's nothing to update manually. New versions getpicked up automatically.

Configuration

Variable	Required	Description
`OPENROUTER_API_KEY`	Yes	Get one at openrouter.ai/keys
`OPENROUTER_IMAGE_OUTPUT_DIR`	No	Where generated images are saved. Defaults to `./pixara-images`

The server just reads these from process.env — there's no .env file loading built in.Whether you're running via npx or from source, set these in the env block of your MCPconfig, as shown above. OPENROUTER_IMAGE_OUTPUT_DIR is optional — leave it out and imagessave to ./pixara-images relative to wherever the server process runs; set it to anabsolute path if you want a predictable location regardless of the client's working directory.

Installing from source

For local development, or if you'd rather not rely on npx:

Requires Node.js 18+.

git clone https://github.com/sizzlebop/pixara-mcp.git
cd pixara-mcp
npm install
npm run build

Then point your MCP config at the built file instead of npx:

{
  "mcpServers": {
    "pixara": {
      "command": "node",
      "args": ["/absolute/path/to/openrouter-image-mcp/dist/index.js"],
      "env": {
        "OPENROUTER_API_KEY": "sk-or-v1-your-key-here",
        "OPENROUTER_IMAGE_OUTPUT_DIR": "/absolute/path/to/wherever/you/want/images"
      }
    }
  }
}

Tools

`pixara_generate_image`

Text-to-image. Required: model, prompt. Optional: n, resolution, aspect_ratio,size, quality, output_format, background, output_compression, seed,provider_options, output_dir, filename_prefix.

Don't combine size with resolution/aspect_ratio — pick one or the other, the tool willreject the call with a clear message if you mix them.

`pixara_edit_image`

Same params as generate_image, plus a required input_references array. Each entry is oneof:

{ "source": "file", "path": "/path/to/photo.png" }
{ "source": "url", "url": "https://example.com/photo.jpg" }
{ "source": "base64", "data": "<base64>", "media_type": "image/png" }

`pixara_list_image_models`

Read-only, free (no image billing). Filter by filter (substring), provider, or capabilitybooleans (supports_img2img, supports_streaming, supports_transparent_background).Paginated with limit/offset.

`pixara_get_model_details`

Read-only, free. Pass a model slug, get back per-provider pricing and exactly whichparameters/passthrough options that provider supports. Worth calling before you useprovider_options, since unsupported params get silently dropped or rejected by the API.

How it decides where to save images

Every generate/edit call decodes the base64 image(s) OpenRouter returns and writes them toOPENROUTER_IMAGE_OUTPUT_DIR (or a per-call output_dir override), named{prefix}-{timestamp}-{index}.{ext}. The extension follows output_format, except forvector output (Recraft's SVG models), which is detected via the response's media_type andwritten as .svg regardless of what output_format was requested.

Limitations

No SSE streaming support yet (see Roadmap)
Model capabilities vary a lot by provider, and OpenRouter's catalog moves fast — alwaystrust pixara_list_image_models/pixara_get_model_details over any hardcoded list
This is new — OpenRouter's Image API has only been out a couple of weeks, so expect modelIDs and params to shift over time

License

Apache 2.0 — see LICENSE.

Made with 💖 by Pink Pixel

Pixara MCP Server