Getting started

From zero to your first call in 60 seconds.

OpusGate is a drop-in replacement for the Anthropic and OpenAI APIs at a fraction of the price. Point any compatible tool at https://api.opusgate.dev and you're done.

Create an account

Email + password. Sign up →

Top up your balance

Minimum $2, refundable within 14 days. Add credits →

Issue an API key

Shown once. Paste into your tool. Generate key →

Fastest setup — one command

Grab a key from the Keys page, run the command for your OS, paste the key when asked — done. The script installs Claude Code if it's missing (checksum-verified download of the official binary that works even where claude.ai is geo-blocked), connects it to OpusGate (~/.claude/settings.json, an existing file is backed up to .bak), and never sends your key anywhere except that local file.

Windows (PowerShell)

PowerShell

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

macOS / Linux

Bash

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

Then just run claude (on Windows — in a new terminal). Piping scripts from the internet? Right to be careful — read the source first: install.ps1 / install.sh.

Set up Claude Code

Pick whichever fits your workflow. Both share the same config file at ~/.claude/settings.json, so you can mix and match later. This is the condensed version — the full Claude Code guide covers model-slot overrides and troubleshooting.

Claude Code CLI

Terminal · macOS, Linux, Windows

npm install -g @anthropic-ai/claude-code

Then run claude in any folder. Config flows from settings.json below.

VS Code extension

Graphical · VS Code 1.98+

Install in VS Code Or open Marketplace ↗

Both modes (graphical panel + integrated terminal CLI) share the same settings.json below.

Drop-in `settings.json`

Both the CLI and the VS Code extension read this file. Create it (or merge into the existing one), paste your API key, and restart Claude Code.

File location

macOS / Linux~/.claude/settings.jsonWindows%USERPROFILE%\.claude\settings.json

Paste this in

{
  "$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"
  }
}

Replace sk-og-... with your key from the Keys page. Use ANTHROPIC_AUTH_TOKEN (sent as a Bearer token) — that's the right field for a gateway like OpusGate. Note: ANTHROPIC_BASE_URL has no /v1 suffix — Claude Code adds the path itself. The ANTHROPIC_DEFAULT_*_MODEL overrides re-map the Opus / Sonnet / Haiku aliases in /model to OpusGate's model IDs. Already have a settings.json? Just merge the env block in.

VS Code extension: one extra step

Open VS Code settings (Cmd+, / Ctrl+,).
Search for Claude Code: Disable Login Prompt and check it. This stops the extension from trying to sign in with an Anthropic account.
Reload the window (Developer: Reload Window from the Command Palette).

Or just export env vars

If you'd rather not touch a config file, set two environment variables before launching Claude Code.

macOS / Linux

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

Windows (PowerShell)

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

To persist, add the lines to ~/.zshrc, ~/.bashrc, or your PowerShell profile.

Available models & pricing

The model ID is what you put in your SDK call or config (e.g. model: "claude-opus-4.7"). Names look familiar but exact IDs may differ from upstream providers — copy from here to be safe.

Loading catalog…

Using a different tool?

OpusGate is wire-compatible with the Anthropic /v1/messages and OpenAI /v1/chat/completions APIs. Anything that lets you change the base URL will work — Cursor, Cline, Roo Code, Continue, Kilo Code, OpenCode, Aider, and so on.

Point the tool at https://api.opusgate.dev and use your sk-og-... key as the API key. For OpenAI-flavoured tools the base path is https://api.opusgate.dev/v1.

Calling the API directly from code? See endpoints & auth, error codes and rate limits. Billing questions — minimums, bonuses, refunds — live in billing & pricing.

Next →Claude Code