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

generate_image

Generate an image from a text description.

Parameters:

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:

* 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.

1. Resize full source (default 550px wide) — never crop
2. Letterbox with white gutters to canvas width (default 780)
3. 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:

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

Available Models

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