Claude Code

Anthropic's official coding agent (CLI + VS Code extension). The one command below sets everything up; prefer to see each step — the full manual walkthrough follows, with troubleshooting at the end.

irm https://opusgate.dev/install.ps1 | iex

curl -fsSL https://opusgate.dev/install.sh | bash

Manual setup

Everything the installer does, by hand — install, then permanent config via settings.json, then run.

1. Install Claude Code

Skip if claude --version already works.

curl -fsSL https://claude.ai/install.sh | bash
claude --version

irm https://claude.ai/install.ps1 | iex

After the installer finishes, fully close and reopen PowerShell, then check claude --version. Prefer npm? npm install -g @anthropic-ai/claude-code works on all platforms.

2. Recommended: permanent setup via settings.json

Claude Code reads ~/.claude/settings.json on every start — configure once and forget. Both the CLI and the VS Code extension use the same file.

{
  "$schema": "https://json.schemastore.org/claude-code-settings.json",
  "env": {
    "ANTHROPIC_BASE_URL": "https://api.opusgate.dev",
    "ANTHROPIC_AUTH_TOKEN": "sk-og-...",
    "ANTHROPIC_DEFAULT_OPUS_MODEL": "claude-opus-4.8",
    "ANTHROPIC_DEFAULT_SONNET_MODEL": "claude-sonnet-4.6",
    "ANTHROPIC_DEFAULT_HAIKU_MODEL": "claude-haiku-4.5",
    "DISABLE_TELEMETRY": "1",
    "DISABLE_ERROR_REPORTING": "1"
  }
}

Already have a settings.json? Merge the env block into it instead of replacing the file.

3. What this config does

"ANTHROPIC_BASE_URL": "https://api.opusgate.dev",
"ANTHROPIC_AUTH_TOKEN": "sk-og-..."

Routes every request to OpusGate instead of the official Anthropic endpoint. Use ANTHROPIC_AUTH_TOKEN (sent as a Bearer token), not ANTHROPIC_API_KEY — the token variant is the correct field for a gateway and also stops Claude Code from asking you to log in to Anthropic.

"ANTHROPIC_DEFAULT_OPUS_MODEL": "claude-opus-4.8",
"ANTHROPIC_DEFAULT_SONNET_MODEL": "claude-sonnet-4.6",
"ANTHROPIC_DEFAULT_HAIKU_MODEL": "claude-haiku-4.5"

Claude Code's /model menu has three fixed slots — Opus, Sonnet, Haiku. These variables re-map each slot to an OpusGate model ID, so the standard picker keeps working. Any ID from the catalog is valid, e.g. pin the Opus slot to claude-opus-4.7 if you prefer it.

DISABLE_TELEMETRY and DISABLE_ERROR_REPORTING stop Claude Code's usage analytics and crash reports to Anthropic. They do not affect functionality — keep or drop as you like.

4. Non-interactive install (CI, scripts)

The one-command installer from the top of this page can also run unattended — pass the key inline instead of typing it at the prompt:

$env:OPUSGATE_KEY = "sk-og-..."; irm https://opusgate.dev/install.ps1 | iex

curl -fsSL https://opusgate.dev/install.sh | OPUSGATE_KEY="sk-og-..." bash

5. Run

claude

That's it — the config is picked up automatically. To verify the connection, ask it anything; the first reply confirms billing against your OpusGate balance (check Transactions). Switch models any time with /model.

6. One-off run without settings.json

For a quick test only — the variables live until you close the terminal.

export ANTHROPIC_BASE_URL="https://api.opusgate.dev"
export ANTHROPIC_AUTH_TOKEN="sk-og-..."
claude

$env:ANTHROPIC_BASE_URL = "https://api.opusgate.dev"
$env:ANTHROPIC_AUTH_TOKEN = "sk-og-..."
claude

7. VS Code extension: one extra step

1. Install the extension: open in VS Code or via the Marketplace.
2. Make sure ~/.claude/settings.json from step 2 exists — the extension reads the same file.
3. In VS Code settings (Ctrl/Cmd + ,) enable Claude Code: Disable Login Prompt so it stops offering an Anthropic sign-in.
4. Reload the window (Developer: Reload Window).

8. Troubleshooting

Close PowerShell completely and open a new window — PATH updates don't reach already-open terminals. Still failing? Run where.exe claude: if nothing is found, re-run the install script from step 1.

That means it doesn't see your token. Check that the key is set as ANTHROPIC_AUTH_TOKEN (not ANTHROPIC_API_KEY) and that settings.json is valid JSON — a trailing comma silently breaks the whole file. If you previously logged in with an Anthropic account, run /logout once.

The key was mistyped, revoked, or has whitespace around it. Keys are shown once at creation — if in doubt, issue a new one. All error responses are listed on the error codes page.

Almost always an empty balance. Top up and retry — no restart needed.