# Using 4AICode in VS Code / Cursor / Windsurf

Anthropic’s official **Claude Code extension** (2.0+) supports configuring a relay URL directly in VS Code’s `settings.json`, **without relying on system environment variables**. Usage is exactly the same on Windows / macOS / Linux.

Cursor and Windsurf are both based on VS Code, so the configuration method is the same.

## 1. Install the Extension

Search for **Claude Code** in the Extensions panel and install the one published by **Anthropic**.

## 2. Open settings.json

Opening it through the Command Palette is the most reliable and fastest method.

1. Open the Command Palette:
   - Windows / Linux: `Ctrl + Shift + P`
   - macOS: `Cmd + Shift + P` (⇧⌘P)
2. Type **Preferences: Open User Settings (JSON)** and press Enter.

> If `Ctrl/Cmd + Shift + P` does not work (commonly because it is intercepted by an input method or another tool), use `Ctrl + P` / `Cmd + P` to open the “Quick Open” panel. Type `>` (greater-than sign) as the **first character** in the input box to switch to the Command Palette, then search for the same command.

## 3. Add the Configuration

Add `claudeCode.environmentVariables` to the top-level object in `settings.json`:

```json
{
  "claudeCode.environmentVariables": [
    { "name": "ANTHROPIC_BASE_URL", "value": "https://relay.4aicode.com" },
    { "name": "ANTHROPIC_AUTH_TOKEN", "value": "sk-4ai-xxxxxxxxxxxxxxxx" }
  ]
}
```

If you already have other settings, merge this into them. **Do not nest it under another key**.

To use ChatGPT `gpt-5.6-sol` with extra-high reasoning in the Claude Code panel, add the model and reasoning-effort variables as well:

```json
{
  "claudeCode.environmentVariables": [
    { "name": "ANTHROPIC_BASE_URL", "value": "https://relay.4aicode.com" },
    { "name": "ANTHROPIC_AUTH_TOKEN", "value": "sk-4ai-xxxxxxxxxxxxxxxx" },
    { "name": "ANTHROPIC_DEFAULT_OPUS_MODEL", "value": "gpt-5.6-sol" },
    { "name": "ANTHROPIC_DEFAULT_OPUS_MODEL_NAME", "value": "4AICode GPT 5.6 Sol" },
    {
      "name": "ANTHROPIC_DEFAULT_OPUS_MODEL_SUPPORTED_CAPABILITIES",
      "value": "effort,xhigh_effort,thinking,adaptive_thinking,interleaved_thinking"
    },
    { "name": "ANTHROPIC_MODEL", "value": "opus" },
    { "name": "ANTHROPIC_DEFAULT_HAIKU_MODEL", "value": "gpt-5.4-mini" },
    { "name": "CLAUDE_CODE_EFFORT_LEVEL", "value": "xhigh" }
  ]
}
```

`ANTHROPIC_DEFAULT_OPUS_MODEL` maps Claude Code’s `opus` alias to `gpt-5.6-sol`, and `CLAUDE_CODE_EFFORT_LEVEL=xhigh` corresponds to extra-high reasoning.

To use GPT-6 Astra, set `ANTHROPIC_DEFAULT_OPUS_MODEL` to `gpt-6-astra`; you can also set the display name to `4AICode GPT 6 Astra`.

The gateway selects the upstream service by the requested `gpt-*` or `claude-*` model name. Check the console for current availability.

## 4. Restart VS Code

Fully quit and reopen it (closing the window is not enough; variables are read once when the process starts and will not refresh afterward):

- Windows: `File → Exit` / `Alt + F4`, then check that all `Code.exe` processes have exited in the system tray and Task Manager.
- macOS: `Cmd + Q`
- Linux: `File → Exit`

The same applies to Cursor / Windsurf.

## 5. Verify

Open the Claude Code panel on the left (an Anthropic icon appears after installing the extension) and send `ping`. If it responds, the connection is working.

Then go to [Dashboard → Usage Records](https://4aicode.com/dashboard) to confirm the corresponding requests.

## FAQ

**Q: It still shows the "Welcome to Claude Code" sign-in screen?**

Do not click the three buttons (Claude.ai Subscription / Anthropic Console / Bedrock). Clicking them initiates OAuth with the official service. Afterward, you must run `claude logout` to clear the local login state before returning to 4AICode. Most likely causes:

1. `claudeCode.environmentVariables` is misspelled or nested under another key — check `settings.json`.
2. VS Code was not fully restarted — terminate all `Code.exe` processes in the system tray and Task Manager, then reopen it.
3. You used `ANTHROPIC_API_KEY` instead of `ANTHROPIC_AUTH_TOKEN` — the 2.0 extension recognizes the latter more reliably.

**Q: Will Cursor’s own Chat / Agent conflict with this?**

No. Claude Code is a separate panel. Cursor’s built-in Chat / Agent / Tab use Cursor’s own backend, so they do not affect each other.

**Q: Workspace settings or User settings?**

We recommend configuring it at the **User** level (using **Preferences: Open User Settings (JSON)** above), so all projects share it. If you only want it to apply to one project, use **Preferences: Open Workspace Settings (JSON)**, which writes to `.vscode/settings.json` under the project.

> ⚠️ Do not commit Workspace settings to git, or your token may be exposed.