Griptape Driver: Amazon Bedrock Stable Diffusion

Here's the pitch: you want Stable Diffusion images but your machine can't run the model locally, or you're on a laptop and the fan already screams when you open a browser. Griptape Driver: Amazon Bedrock Stable Diffusion hands your prompt to Amazon's managed Stable Diffusion endpoint and gets an image back over the API. No weights to download, no VRAM, no sampler tuning.

The catch is you need an AWS account with Bedrock enabled and the Stable Diffusion model activated in your region - and you'll pay per image. For anyone already living in AWS, it's a zero-install way to generate; for everyone else, it's a niche unless you have a compliance reason to keep generation in your cloud.

How it works

Like every driver in this pack, this node doesn't draw anything by itself. It's a configuration node: you set the parameters, it builds a Griptape image-generation driver object, and you feed that DRIVER output into a Griptape Run: Prompt Image Generation Task (the "Create Image from Text" node) along with your prompt. That task calls the API and returns the image.

The inputs worth your attention:

• style_preset - Bedrock's Stable Diffusion preset (anime, cinematic, photographic, etc.). Defaults to cinematic; this is where most of the visible difference in output comes from.
• width / height - 64 to 2048, stepped by 64. 512x512 is the sensible default; pushing past ~1024 on the non-turbo models gets slow and expensive.
• seed - set it to reproduce a generation, same as local.

Then the AWS plumbing: aws_access_key_id_env_var, aws_secret_access_key_env_var, and aws_default_region_env_var. Notice the tooltip and the pattern - these take the names of environment variables, not your actual keys. The README walks you through creating an access key in the AWS console; the region variable is required because Bedrock is region-scoped.

Installing

Ships in the ComfyUI Griptape Nodes pack:

• ComfyUI Manager: search "Griptape" → install ComfyUI-Griptape.
• Manual: cd ComfyUI/custom_nodes && git clone https://github.com/griptape-ai/ComfyUI-Griptape, then restart.

The pack installs griptape[all], openai, python-dotenv, and git-hosted extensions. The familiar torch gotcha applies - Griptape declares torch and can clash with ComfyUI's build; if things break, reinstall torch with the CUDA index as the README describes (--extra-index-url https://download.pytorch.org/whl/cu121).

Gotchas

Most failures here are AWS-side, not node-side. "AccessDenied" usually means Bedrock isn't enabled or the model isn't granted in your region; check the Bedrock console's model access page. Missing key errors mean the env vars aren't set - either export them before launching ComfyUI or enter them under Settings → Griptape, which reads them from your environment if they're already there. And remember this is cloud Stable Diffusion, not the local one: you're bounded by Bedrock's model version, so don't expect your favorite community checkpoint's exact look.