mcp-server-grok-image

An MCP (Model Context Protocol) server for xAI's Grok image generation API. Built in Rust, exposes image generation and editing as MCP tools.

Communicates via stdio using JSON-RPC 2.0, like all MCP servers.

Tools

Tool	Description
`generate_image`	Generate an image from a text prompt
`edit_image`	Edit an existing image using natural language instructions
`headshot`	Corporate headshot from a source portrait (pad to 3:2 + fixed edit prompt)
`list_styles`	List available image styles for use with `generate_image`

generate_image

Generate an image from a text description.

Parameters:

Name	Type	Required	Description
`prompt`	string	yes	Text description of the desired image
`model`	string	no	Model to use (default: `grok-imagine-image-2.0`)
`n`	integer	no	Number of images to generate (1-10, default 1)
`aspect_ratio`	string	no	Aspect ratio: `1:1`, `16:9`, `9:16`, `4:3`, `3:4`, `3:2`, `2:3`, `2:1`, `1:2`, `19.5:9`, `9:19.5`, `20:9`, `9:20`, `21:9`, `5:2`, `auto`
`resolution`	string	no	Output resolution: `1k` (~1024px, default) or `2k` (~2048px)
`quality`	string	no	`low`, `medium`, or `auto` (2.0 only; omitted = `auto`. Auto currently serves `low` for generation)
`response_format`	string	no	Output format: `url` (default, temporary) or `b64_json`
`style`	string	no	Style name to apply (use `list_styles` to see options)

When a style is set, the prompt is wrapped in the style's template. For example, with style: "watercolor" and prompt: "a cat on a roof", the API receives "a cat on a roof, as a watercolor painting". Avoid including style language in the prompt itself when using this parameter.

The response includes the resolved prompt so you can see exactly what was sent to the API.

edit_image

Edit an existing image using natural language instructions.

Parameters:

Name	Type	Required	Description
`image_url`	string	no*	URL, base64 data URI, or local file path of the source image. Mutually exclusive with `images`.
`images`	string[]	no*	Up to 5 source images for multi-image editing. Reference them in the prompt as `<IMAGE_0>`, `<IMAGE_1>`, …
`prompt`	string	yes	Natural language edit instructions
`model`	string	no	Model to use (default: `grok-imagine-image-2.0`)
`n`	integer	no	Number of variations to generate (1-10, default 1)
`aspect_ratio`	string	no	Same set as `generate_image`, including `21:9` and `5:2`
`resolution`	string	no	Output resolution: `1k` (~1024px, default) or `2k` (~2048px)
`quality`	string	no	`low`, `medium`, or `auto` (2.0 only; omitted = `auto`. Auto currently serves `medium` for editing)
`response_format`	string	no	Output format: `url` (default, temporary) or `b64_json`

* Provide either image_url or images.

Note: The style parameter is intentionally not available on edit_image -- edit prompts are instructions (e.g. "remove the background"), not descriptions, so wrapping them in style templates would produce nonsense.

headshot

Expand-only portrait fix (Gemini pipeline equivalent on Imagine). Does not reframe pose, cut out hair, or redesign the person.

Resize full source (default 550px wide) — never crop
Letterbox with white gutters to canvas width (default 780)
Call grok-imagine-image-2.0 at quality medium: complete cut-off shoulders if needed; clean solid white background; keep face/hair/pose/clothing/logos

No cutout / no rembg / no transparent alpha — same job as the original Gemini headshot skill.

Parameters:

Name	Type	Required	Description
`image`	string	yes	Local path, http(s) URL, or `data:` URI
`clothing`	string	no	For missing-shoulder fill only
`notes`	string	no	Must-preserve details (glasses, exact logo text, …)
`pronoun`	string	no	`his` / `her` / `their` (default `their`)
`gravity`	string	no	Letterbox gravity (`North` default)
`content_width`	integer	no	Resize width before pad (default `550`)
`canvas_width`	integer	no	Padded width (default `780`)
`resolution`	string	no	`1k` or `2k` (default `2k`)
`output_path`	string	no	Optional final path (also under `save_dir`)
`n`	integer	no	Variations (1–10, default 1)
`quality`	string	no	`low` / `medium` / `auto` (default `medium`)
`model`	string	no	Default `grok-imagine-image-2.0`

Padded intermediate: save_dir/headshot-padded_*.jpg.

list_styles

Returns all available image styles with their name, description, and prompt template. No parameters.

Built-in Styles

Style	Description
`watercolor`	Watercolor painting style
`oil-painting`	Oil painting with visible brushstrokes
`pencil-sketch`	Detailed pencil sketch
`pixel-art`	Retro pixel art
`anime`	Anime style illustration
`pop-art`	Bold pop art style
`art-nouveau`	Art nouveau with flowing organic lines
`cinematic`	Cinematic photography with dramatic lighting
`portrait`	Professional portrait photography
`macro`	Extreme macro photography
`aerial`	Aerial drone photography
`studio`	Studio photography on clean background
`noir`	Dark film noir style
`vintage`	Faded vintage photograph

Available Models

Model	Notes
`grok-imagine-image-2.0` (default)	Optional `quality` (`low` / `medium` / `auto`), up to 5 edit references, `21:9` and `5:2`. Auto currently serves `low` for generation and `medium` for editing.
`grok-imagine-image`	1.0. Still available; no `quality` param.
`grok-imagine-image-quality`	Retires 2026-11-02. After that the slug is served by `grok-imagine-image-2.0` at `quality: low` ($0.01 less per image than the quality model).

Prerequisites

Rust (edition 2024)
An xAI API key from console.x.ai

Setup

Create the config file:

mkdir -p ~/.config/mcp-server-grok-image

Create ~/.config/mcp-server-grok-image/config.toml:

api_key = "xai-..."

Custom Styles

Add custom styles to your config file. Custom styles with the same name as a built-in will override it.

api_key = "xai-..."

[[styles]]
name = "my-style"
description = "My custom look"
template = "{prompt}, in my custom style"

[[styles]]
name = "watercolor"
description = "My watercolor variant"
template = "{prompt}, as a loose expressive watercolor with ink outlines"

Templates must contain the {prompt} placeholder. Any custom style missing it will be skipped with a warning at startup.

Build

cargo build --release

This produces target/release/mcp-server-grok-image.

For development:

cargo build              # debug build
cargo run                # run in dev mode
RUST_LOG=debug cargo run # run with debug logging

MCP Configuration

Add to your Claude Desktop config (~/.config/Claude/claude_desktop_config.json):

{
  "mcpServers": {
    "grok-image": {
      "command": "/path/to/mcp-server-grok-image"
    }
  }
}

Project Structure

src/
  main.rs      process entry (stdio MCP)
  config.rs    TOML / env config
  styles.rs    built-in + custom styles
  grok.rs      xAI request/response types
  params.rs    MCP tool params + validation
  image_io.rs  data URIs, local files, mime, fetch
  headshot.rs  letterbox pad + expand prompt
  server.rs    MCP tools and Grok HTTP

License

MIT