Arc en Ciel help
Set up Arc en Ciel Link
Connect local or hosted Stable Diffusion tools to Arc en Ciel with Link Keys, sidecars, and model inventory.
Before you start
- A signed-in account.
- A supported local or hosted tool such as the Arc en Ciel Link Forge or ComfyUI extension.
- Permission to create or manage Link Keys.
Quick answer
- Install the local Link integration, create a dedicated Link Key, paste it into the local tool, then restart or reload the tool.
- Use the Link panel to confirm connection state, local bases, and downloaded resources before starting generation work.
- Keep Link Keys out of screenshots, shared workflows, Discord messages, and committed config files.
What Link does
Arc en Ciel Link is the bridge between your account and local Stable Diffusion tooling. It can help local tools understand which resources you downloaded, which base models exist locally, and how sidecar metadata maps Arc en Ciel resources to files on disk. Link is for local convenience; it is not a reason to expose API keys, Link Keys, or local paths publicly.
Setup steps
- Install the supported local integration, such as the Arc en Ciel Link ComfyUI extension.
- Open Arc en Ciel settings or the Link panel and create a Link Key with the smallest scope the integration needs.
- Copy the key once and store it in the local extension configuration, not in screenshots or shared workflows.
- Start or reload the local tool so it can connect to Arc en Ciel.
- Check the Link panel or extension logs for connection state.
- Confirm local base models and downloaded resources appear as expected before starting generation workflows.
Google Colab and hosted WebUIs
A browser tab cannot call a loopback bridge inside a separate Colab runtime. Hosted workers instead connect outbound to Arc en Ciel with the same dedicated Link Key; port 8501 stays private and does not need a tunnel.
- Create a dedicated Link Key in the Arc en Ciel Link panel and copy it once.
- Add it to the Colab Secrets panel with the name ARCENCIEL_LINK_KEY. Do not paste it into a shared notebook cell.
- Run the notebook Link setup cell before starting Forge/WebUI. It loads the secret into ARCENCIEL_LINK_KEY and enables the worker for that runtime.
- On arcenciel.io, store the same key and leave its endpoint set to Remote / Colab, then press Connect.
- Confirm the extension log reports protocol 2 and the Link panel becomes connected before queueing a model.
| Piece | Purpose |
|---|---|
| Link Key | Authenticates the local integration to your account for Link worker and inventory actions. |
| Sidecar metadata | Stores resource metadata next to local files so tools can map names, hashes, and source context. |
| Local base inventory | Tells the integration which base models are available locally. |
| Download history | Helps connect Arc en Ciel resources to files you previously saved. |
Security checklist
- Use a dedicated Link Key - Do not reuse a broad API key for local Link. Link workers should use Link Keys.
- Do not commit config files - Local extension settings can contain secrets or machine-specific paths.
- Rotate keys after sharing logs - If a key may have appeared in a screenshot or log, delete it and create a new one.
Setup problems
Key rejected
Likely cause: Copied incorrectly, expired, deleted, or missing required scope.
Fix: Create a fresh Link Key and paste it into the local integration without extra whitespace.
Connected but no local models appear
Likely cause: Local base directory or sidecar path is not configured.
Fix: Check extension settings and rescan local inventory.
Colab worker stays offline
Likely cause: The runtime started before ARCENCIEL_LINK_KEY was loaded, or the browser key and Colab secret do not match.
Fix: Set the Colab secret, run the Link setup cell before the WebUI startup cell, and restart the runtime after changing the key.
Wrong model matched
Likely cause: Hash or sidecar metadata is missing or stale.
Fix: Regenerate sidecars or verify hashes in the local folder.