mcp-openai-images-audio 0.1.1

MCP server exposing OpenAI gpt-image-2 image generation and editing as a single tool for Claude Code and other MCP clients.

mcp-openai-images-audio

v0.1.0

MCP server that exposes OpenAI's gpt-image-2 and gpt-image-1.5 to Claude Code as a single tool. Generate, edit, or compose images straight from a chat. Files are written to disk; the model never returns base64 to your context.

This isn't a wrapper for everything OpenAI does. It's one tool: image. That's intentional.

One call, size: 2048x1152, quality: high, no references — produced this UI mockup. Real readable typography, real-looking code preview, accurate Instagram visual language. That's the level you should expect.

Install

pip install mcp-openai-images-audio

Or run directly without installing:

uvx mcp-openai-images-audio

Connect to Claude Code

claude mcp add openai-images \
  --scope user \
  -e OPENAI_API_KEY=sk-... \
  -- uvx mcp-openai-images-audio

Important:

1. Organization verification is mandatory for gpt-image-2. Verify at https://platform.openai.com/settings/organization/general. Takes a few minutes, propagates within 15 minutes.
2. The API key needs billing credit. Without it you get a 400 with billing_hard_limit_reached.
3. The server runs over stdio. No HTTP, no separate process to keep alive — Claude Code starts and stops it for you.

How the tool works

One tool, three modes selected by references_paths:

• empty / not passed → /v1/images/generations (text → new image)
• 1 path → /v1/images/edits (modify that image)
• 2..16 paths → /v1/images/edits (compose with labeled references)

The server picks the model on its own:

• background='transparent' → gpt-image-1.5 (gpt-image-2 currently rejects alpha — confirmed regression in OpenAI's docs)
• everything else → gpt-image-2

The actual model used is reported in the response.

Parameters

Param	Required	Notes
prompt	yes	English. Structure matters — see the prompting guide.
output_path	yes	Absolute path. Parent must exist. File must NOT exist. Extension picks format: .png / .jpg / .jpeg / .webp.
size	yes	One of: 1024x1024, 1536x1024, 1024x1536, 2048x2048, 2048x1152, 1152x2048, 3840x2160, 2160x3840. No default — pick deliberately.
references_paths	no	List of absolute paths, up to 16 files, each ≤50 MB.
quality	no	low / medium / high. Omit for default (auto).
input_fidelity	no	low / high. Pass high for face-preserving edits.
background	no	auto (default) / opaque / transparent.

The server hard-codes moderation=low, n=1, output_compression=100. Not configurable.

Prompting guide

Before the first call, Claude reads the resource image-guide://full. It covers:

• prompt structure (medium → subject → scene → composition → lighting → texture → constraints)
• photorealism rules (camera language, anti-words like "8K", "masterpiece")
• text rendering inside images
• edit/compose modes with role labeling
• size selection per use case
• when to set quality and input_fidelity
• the transparent-background trap — if you write "transparent background" in the prompt instead of passing background='transparent', the model paints the editor checkerboard pattern into RGB. The image looks transparent in a thumbnail but isn't.

The server detects the checkerboard trap after writing the file and returns alpha_appears_baked: true. Don't trust the visual preview without checking that flag.

Response

{
  "path": "/abs/path.png",
  "bytes": 1219063,
  "size": "1024x1024",
  "model": "gpt-image-2",
  "mode": "generate",
  "has_alpha": false,
  "alpha_used": null,
  "tokens_used": 289,
  "estimated_cost_usd": 0.0117
}

If transparency was requested, alpha_appears_baked is also included. If anything looks wrong, a warnings array is added with human-readable text.

Logs

Each call appends one JSON line to ~/.cache/mcp-openai-images-audio/log.jsonl. The log rotates at 10 MB; one previous file is kept as log.jsonl.1.

tail -f ~/.cache/mcp-openai-images-audio/log.jsonl

Recommendations

• For UI mockups with readable text, use size: 3840x2160 and quality: high. Smaller sizes blur small fonts.
• For logos / icons that need transparency, set background: 'transparent' — the server will route to gpt-image-1.5 automatically. Don't try to ask for transparency in the prompt.
• For portrait edits, pass input_fidelity: 'high'. Otherwise the face drifts across iterations.
• For drafts, use quality: 'low' (~$0.006/image). Promote to high only when the result has to be final.
• Don't pass quality at all for most cases. The default is good enough.
• The model gives most weight to the first ~50 words of the prompt. Put the medium and subject up front.

Pricing notes

Cost depends on size and quality. Typical 1024×1024 cases:

• quality: low → ~$0.006
• quality: medium → ~$0.05
• quality: high → ~$0.21

4K is roughly 4× the price of 2048×1152. The tool reports estimated_cost_usd per call; treat it as approximate — it tracks OpenAI's published per-token rates.

Build from source

git clone https://github.com/eduard256/mcp-openai-images-audio.git
cd mcp-openai-images-audio
uv sync
uv run mcp-openai-images-audio

Tests:

uv run --extra dev pytest

Known limitations

1. gpt-image-2 does not support background: transparent. The server falls back to gpt-image-1.5 automatically. Quality on transparent calls is therefore gpt-image-1.5 quality, not the flagship.
2. n is hard-coded to 1. To get multiple variants, call the tool multiple times in parallel.
3. No tts / audio tool yet despite the package name. Coming in a later version.
4. No streaming partial images. The tool returns when the file is fully written.

License

MIT