I wrote this plugin mainly to simplify my own workflow, allowing access to LLM or image generation through standardized OpenAI interfaces. Recently, I've been mainly using this node to play with Gemini-2.5-Flash-Image generation (haven't tested the official Gemini interface, I'm connecting to an OpenAI-compatible endpoint), and the results are quite good.

Recent Updates

2026-9-7 Aspect Ratio Labels: All size presets in the image node now include visual aspect ratio annotations, e.g. 1254x1254(1:1,1K), 1024x1536(2:3,1K), 1672x941(16:9,1K).
2025-11-21 v1.0.7 New Models & Aspect Ratio Support: Added support for models like nano-banana and nano-banana-pro, and allows using aspect ratios for size in non-compatibility mode.
2025-9-13 v1.0.6 The image node now supports JPG type for image URI content to be compatible with some seedream4 API requests.
2025-9-3 v1.0.5 Model Memory & Management: Added a persistent model list for both image and text nodes, with major code refactoring for maintainability.
2025-9-3 v1.0.4 Multi-Image Return: The image node can now process and output multiple images at once, resolving size mismatch and data type errors.
2025-9-3 v1.0.3 Fixed a bug in stream response handling and improved debug logging.
2025-9-3 v1.0.2 Added OpenRouter support (with streaming), debug info merged to debug.log
2025-9-2 v1.0.1 Optimized error messages in debug mode, added support for free models on OpenRouter
2025-9-2 v1.0 release, tested integration with tuzi and GB works perfectly
2025-8-31 Plugin initialization

✨ Key Features

🌐 Multiple API Sources Support

Flexible Configuration: Support multiple API providers via .env file, so if you have multiple token channels you don't have to switch back and forth, they can be shared.
Dynamic Selection: Switch between providers without restarting ComfyUI
Model Memory & Management: Select favorite models from a dropdown or add a new one in the custom_model field. Run it once to save it automatically for future use.

🖼️ OpenAI Image Node (`flexai:openai_image`)

Dual-Mode Operation:

Edit Mode: Provide 1-4 images → Uses images.edit API, i.e., /v1/images/edits endpoint
Generate Mode: No images → Uses images.generate API, i.e., /v1/images/generations endpoint

Compatibility Mode: Generate images via chat endpoint, compatible with OpenRouter and other third-party OpenAI-compatible interfaces, with streaming support, i.e., the standard /v1/chat/completions endpoint.

Extended Model Support:

The interface now supports new models like nano-banana and nano-banana-pro.
You can call them directly via the custom_model field. For instance, when using services like api.tu-zi.com, you can enter gemini-3-pro-image-preview.
These models support both standard image generation and compatibility modes.

💬 OpenAI Text Node (`flexai:openai_text`)

Multimodal Support:

Text-Only Mode: Standard text generation
Vision Mode: Support image input for visual Q&A
Hybrid Mode: Combined text and image analysis

Multimodal Text Generation:

Pure text or vision-language understanding
Support 1-4 reference images with auto-scaling
Streaming and non-streaming modes
Debug Mode: Complete JSON logging for all operations

Quick Start

Installation

Clone to ComfyUI custom nodes:

cd ComfyUI/custom_nodes
git clone https://github.com/Semonxue/Comfyui-flexai.git

Install dependencies:

cd Comfyui-flexai
pip install -r requirements.txt

Configure providers (see Configuration section)
Restart ComfyUI

Configuration

Create a .env file in the plugin root directory, or copy and rename the .env.example file.

Single Provider

OPENAI_API_KEY=your_openai_api_key_here
OPENAI_API_BASE=https://api.openai.com/v1  # Optional

Multiple Providers (Recommended)

# Define provider list
OPENAI_PROVIDERS=openai,anthropic,custom

# OpenAI
OPENAI_API_KEY_openai=sk-your-openai-key
OPENAI_API_BASE_openai=https://api.openai.com/v1

# Anthropic (via OpenAI-compatible endpoint)
OPENAI_API_KEY_anthropic=sk-your-anthropic-key  
OPENAI_API_BASE_anthropic=https://api.anthropic.com/v1

# Custom endpoint
OPENAI_API_KEY_custom=your-custom-key
OPENAI_API_BASE_custom=https://your-api.example.com/v1

Node Parameters

Image Node (`flexai:openai_image`)

Parameter	Type	Description
`provider`	Choice	API provider selection
`model`	String	Model name (e.g., `dall-e-3`, `dall-e-2`)
`prompt`	String	Generation/editing prompt
`image_1-4`	Image	Optional images (edit mode if any provided)
`size`	Choice/String	Output size preset with aspect ratio label (e.g. `1254x1254(1:1,1K)`, `1024x1536(2:3,1K)`, `1672x941(16:9,1K)`). The dropdown offers all common ratios across 1K/2K/4K tiers. Use `custom_size` for free-form input. Aspect Ratio Support: For specific models like `nano-banana` and `nano-banana-pro` in non-compatibility mode, this field accepts aspect ratios. Supported ratios and their corresponding resolutions are: `1x1` → `1024x1024` `2x3` → `832x1248` `3x2` → `1248x832` `3x4` → `864x1184` `4x3` → `1184x864` `4x5` → `896x1152` `5x4` → `1152x896` `9x16` → `768x1344` `16x9` → `1344x768` `21x9` → `1536x672`
`compatibility_mode`	Boolean	Compatibility Mode: Enable chat endpoint for image generation, compatible with OpenRouter and other third-party services
`stream`	Boolean	Enable streaming mode
`debug`	Boolean	Enable detailed debug logging

Text Node (`flexai:openai_text`)

Parameter	Type	Description
`provider`	Choice	API provider selection
`model`	String	Model name (e.g., `gpt-4o`, `gpt-3.5-turbo`)
`system_prompt`	String	System message
`user_prompt`	String	User message
`image_1-4`	Image	Optional reference images
`max_tokens`	Integer	Maximum response tokens
`temperature`	Float	Sampling temperature (0.0-1.0)
`stream`	Boolean	Enable streaming mode
`debug`	Boolean	Enable detailed debug logging

Example Workflows

Product Placement

Download Workflow

Figure Redress