Skip to main content
ValarCode routes VS Code through GitHub Copilot Chat’s bring-your-own-key Custom Endpoint provider. Enabling registers a Valar provider group in Copilot Chat, and you pick a Valar model from its model picker. The group speaks the Anthropic Messages API; the gateway maps whatever model it sends to the target your routing resolves to. See Set up ValarCode for the shared setup and the client-id model.
The VS Code integration uses the copilot harness, so the command is valar copilot. valar vscode is an alias you can use interchangeably; attribution is recorded under the copilot harness either way.

​
Prerequisites

  • VS Code (the stable build) with GitHub Copilot Chat signed in, and a version new enough to offer the Custom Endpoint provider. Insiders and forks keep their own config and are not routed.
  • A Valar coding key (vlrcode_…) and the valar CLI (install).

​
Enable routing

Run once per machine:
Then reload the VS Code window and pick a Valar model in Copilot Chat’s model picker. If the group is not listed yet, reload again. Check the state any time:

​
What gets written

The CLI registers a provider group in Copilot Chat’s model config, chatLanguageModels.json, in the VS Code user directory (~/Library/Application Support/Code/User on macOS, ~/.config/Code/User on Linux), plus one file per additional VS Code profile under profiles/*/. The file is a JSON array of provider groups; the CLI adds a group named Valar:
In detail, enabling:
  • Registers a Valar group under the built-in customendpoint vendor, with apiType: "messages" so the group speaks the Anthropic Messages dialect. The group’s models list is the picker; you choose a Valar model there yourself.
  • Writes the full per-model endpoint https://api.valarhq.ai/v1/messages on each model, since this vendor has no separate base-URL field.
  • Carries the coding key in the x-api-key request header rather than the vendor’s apiKey field. That field is stored in the OS keychain and cannot be populated by an external writer, so the key rides as a request header instead; the gateway authenticates it like a bearer token.
  • Adds X-Valar-Harness: copilot, X-Valar-Client-Id and X-Valar-Cli-Version to each model’s requestHeaders for attribution.
On the first enable, the files it touches are snapshotted to ~/.valar/copilot/backup.json. A VS Code profile you create later is routed by the next on and un-routed by off on the Valar marker, without a snapshot of its own.
The client id defaults to your OS username, so the header reads X-Valar-Client-Id: jdoe. Use --user-id RANDOM for an opaque vc_… id instead. See per-engineer attribution.
A chatLanguageModels.json that contains comments (JSONC) is skipped and reported rather than rewritten, so a hand-edited file is never clobbered. Remove the comments and re-run on to route that profile.

​
Turn off routing

This restores the pre-enable snapshot and removes the Valar group from any profile it was added to. Reload the VS Code window if the Valar models are still listed in Copilot Chat.

​
Next steps

Model routing

How cohorts and the split decide which model serves each request.

Analytics

Per-engineer usage and savings, attributed by client id.