Chatgpt Web Prompt MCP

ChatGPT Web Prompt MCP Bridge

Use this when the user wants to send image-generation prompts (optionally with local reference images) into ChatGPT Web through a real Chrome window, without downloading generated images.

Current install

Primary ChatGPT Web prompt-forwarding MCP server path:

~/.hermes/chatgpt-web-prompt-mcp/server.mjs

Legacy Claude MCP bridge path, now updated as a compatibility wrapper:

~/.hermes/scripts/hermes_image_mcp.py

The legacy hermes-image bridge now exposes both the original Hermes generate_image flow and ChatGPT Web tools:

generate_image
image_backend_status
submit_image_prompt
get_latest_generated_images
download_latest_generated_images

Hermes MCP server config name:

chatgpt_web_prompt

Hermes tool name after restart/discovery:

mcp_chatgpt_web_prompt_submit_image_prompt

Claude Code server command:

node ~/.hermes/chatgpt-web-prompt-mcp/server.mjs

Required runtime state

A real Google Chrome window must be open with CDP enabled and logged into ChatGPT:

npm run login

This starts Chrome with:

CDP endpoint: http://127.0.0.1:9222
profile dir: ~/chrome-chatgpt-debug

Keep that Chrome window open while using the tool.

Hermes gateway / Telegram usage

The MCP server is configured in ~/.hermes/config.yaml as mcp_servers.chatgpt_web_prompt. MCP tools are discovered at process startup, so if Telegram gateway or a Hermes session cannot see the tool, restart the gateway / start a new session.

Expected tool name in Hermes:

mcp_chatgpt_web_prompt_submit_image_prompt

Natural-language trigger examples for Telegram:

• "Через chatgpt web prompt mcp отправь промпт: ... preset poster"
• "Используй mcp_chatgpt_web_prompt_submit_image_prompt с reference_image_paths [...]"

Claude Code integration

Preferred MCP server name for Claude Code:

chatgpt-web-prompt

Tool names inside Claude for the preferred server:

submit_image_prompt
get_latest_generated_images
download_latest_generated_images

The older configured Claude MCP server is:

hermes-image

It has been updated as a compatibility bridge and now exposes:

generate_image
image_backend_status
submit_image_prompt
get_latest_generated_images
download_latest_generated_images

So Claude can use either chatgpt-web-prompt.submit_image_prompt or hermes-image.submit_image_prompt depending on which MCP server is visible in that session.

Configure Claude Code with:

claude mcp add chatgpt-web-prompt \
  -- node ~/.hermes/chatgpt-web-prompt-mcp/server.mjs

Or JSON config:

{
  "mcpServers": {
    "chatgpt-web-prompt": {
      "command": "node",
      "args": ["~/.hermes/chatgpt-web-prompt-mcp/server.mjs"],
      "env": {
        "CHATGPT_WEB_CDP_ENDPOINT": "http://127.0.0.1:9222"
      }
    }
  }
}

In Claude Code, reference images must be local files. If the user provides/creates an image, Claude should save or locate it on disk first, then call submit_image_prompt with reference_image_paths containing absolute paths. Preferred paths are under ~/... because Chrome runs as macOS user the Chrome user.

Claude Code tools exposed by this server:

submit_image_prompt
get_latest_generated_images
download_latest_generated_images

Send prompt + reference images

Use the chatgpt-web-prompt MCP tool `submit_image_prompt`.
Prompt: "Create a sticker character in this brand style."
Preset: square
Reference images: /absolute/path/to/reference.png

Tool call shape Claude should produce:

{
  "prompt": "Create a sticker character in this brand style.",
  "preset": "square",
  "reference_image_paths": [
    "/absolute/path/to/reference.png"
  ],
  "submit": true
}

If Claude only has an image attachment but no path, instruct it to first write/copy the image into a local file such as:

~/Desktop/<project>/references/<name>.png

then pass that path in reference_image_paths.

Let Claude see generated images

After ChatGPT Web generates images, Claude can call:

{
  "max_images": 4,
  "include_image_content": true,
  "save": true,
  "save_dir": "~/Downloads/chatgpt-images"
}

using tool:

get_latest_generated_images

This returns:

• a JSON text summary with dimensions, mime type, byte size, and saved paths;
• MCP image content items, so Claude Code can visually inspect the generated images immediately;
• saved files under save_dir when save=true.

If Claude only needs files and does not need to inspect pixels, use:

download_latest_generated_images

with:

{
  "max_images": 4,
  "save_dir": "~/Downloads/chatgpt-images"
}

Typical Claude Code workflow:

1. Call submit_image_prompt with prompt and optional reference_image_paths.
2. Wait until ChatGPT Web visibly finishes generation.
3. Call get_latest_generated_images to see the results and save them.
4. If needed, call submit_image_prompt again with revision instructions.

Tool arguments

{
  "prompt": "image prompt text",
  "preset": "poster",
  "aspect_ratio": "portrait",
  "reference_image_paths": ["/absolute/path/to/ref.png"],
  "submit": true,
  "prefix": "Generate an image from this prompt.",
  "cdp_endpoint": "http://127.0.0.1:9222"
}

• prompt is required.
• preset is preferred and overrides the basic aspect-ratio instruction.
• aspect_ratio is backward-compatible fallback: landscape, square, portrait.
• reference_image_paths is optional, local absolute paths readable by macOS user the Chrome user; max 10 images.
• submit=false uploads refs and inserts prompt without pressing Enter.
• prefix defaults to Generate an image from this prompt.; for exact user-authored prompts, set prefix to an empty string if the wrapper should not prepend its own instruction.

Exact-prompt forwarding pattern

When the user asks to "send this prompt" and especially when the prompt already contains its own parameters, do not use the default prefix / preset behavior unless the user requested it: send_prompt.mjs prepends text such as "Generate an image..." and aspect-ratio instructions, which can unintentionally change the prompt. For exact forwarding:

1. Save the user's prompt verbatim to a temp .txt file to preserve line breaks and avoid shell quoting problems.
2. Ensure reference images are absolute paths readable by Chrome's macOS user. If the attachment is under ~/.hermes/desktop-attachments/, copy it into the working project folder under ~/... and use that copy.
3. Connect to Chrome CDP (http://127.0.0.1:9222), upload the reference via the last input[type="file"], wait a few seconds for thumbnail/upload preparation, insert the exact prompt text into the composer, and press Enter.
4. Report the ChatGPT conversation URL, submitted status, reference image path, and prompt character count.

This direct Playwright pattern is preferred over the MCP wrapper for exact user-authored prompts because it avoids automatic prompt rewriting while still using the same real Chrome/CDP bridge.

Available presets:

landscape, square, portrait, widescreen, ultrawide, story, poster,
book_cover, banner, profile, thumbnail, product

Troubleshooting

Detailed Claude Code tool-visibility notes live in references/claude-code-visibility.md.

• Tool not found in Telegram: restart gateway (hermes gateway restart or /restart from gateway if available) because MCP discovery happens at startup.
• Claude Code says it only sees the old tool list: restart Claude Code completely. MCP stdio servers are spawned and tool schemas are cached at Claude startup; editing server.mjs does not update a running Claude session. Kill stale node ~/.hermes/chatgpt-web-prompt-mcp/server.mjs processes if needed, then start Claude again.
• Claude Code launched with --allowed-tools may hide this server unless the tools are explicitly allowed. Allow names are typically:
  • preferred server:
    • mcp__chatgpt-web-prompt__submit_image_prompt
    • mcp__chatgpt-web-prompt__get_latest_generated_images
    • mcp__chatgpt-web-prompt__download_latest_generated_images
  • legacy hermes-image compatibility server:
    • mcp__hermes-image__generate_image
    • mcp__hermes-image__image_backend_status
    • mcp__hermes-image__submit_image_prompt
    • mcp__hermes-image__get_latest_generated_images
    • mcp__hermes-image__download_latest_generated_images
• Verify the MCP server itself exposes all tools with a tools/list smoke test; current expected tools are submit_image_prompt, get_latest_generated_images, and download_latest_generated_images.
• Chrome not connected: run npm run login, log into ChatGPT, keep the Chrome window open.
• Reference upload fails: confirm the file path is absolute and under ~/..., and that ChatGPT UI supports attachments in the current chat/model.
• Do not use the old Playwright Firefox/Nightly flow; it triggered CAPTCHA loops. This bridge uses real Chrome CDP.