Claude Code & Codex

Home · Getting Started · Configuration · API Reference · Claude Code & Codex

Claude Code

Automatic setup

Run the setup wizard with the Claude Code step enabled:

./target/release/ghc-proxy --setup --claudecode

This patches ~/.claude/settings.json, merging env.ANTHROPIC_BASE_URL and env.ANTHROPIC_API_KEY so Claude Code routes its Anthropic API calls through the proxy. Existing settings are preserved — the base URL is updated, keys are added only when missing, and the file is left untouched if it is not valid JSON.

Manual setup

Set both ANTHROPIC_BASE_URL and ANTHROPIC_API_KEY in ~/.claude/settings.json:

{
  "env": {
    "ANTHROPIC_BASE_URL": "http://127.0.0.1:8314",
    "ANTHROPIC_API_KEY": "ghc-proxy"
  }
}

Or export it in your shell before launching Claude Code:

export ANTHROPIC_BASE_URL="http://127.0.0.1:8314"
export ANTHROPIC_API_KEY="ghc-proxy"

Mapping Claude Code’s models

Claude Code sends specific model names (for example claude-opus-4-7[1m]). Use model mappings to route those to whichever Copilot model you want. For example, to always use Claude Opus 4.8 with its native 1M context:

model_mappings:
  exact:
    claude-opus-4-8: claude-opus-4.8
  prefix:
    claude-opus-4-7: claude-opus-4.8

Restart the proxy after editing config.yaml — mappings are read at startup.

Codex CLI

The Codex /v1/responses endpoint is supported with adapters that make the upstream Copilot Responses API behave like the Codex client expects:

Automatic setup

./target/release/ghc-proxy --setup --codex

This patches ~/.codex/config.toml, adding a model_providers.ghc-proxy block (pointing at http://127.0.0.1:8314/v1) and selecting it. Existing settings are preserved, and the file is left untouched if it is not valid TOML.

Manual setup

Point the Codex CLI at the proxy’s base URL:

export OPENAI_BASE_URL="http://127.0.0.1:8314/v1"

Gemini CLI

Configure the Gemini CLI automatically:

./target/release/ghc-proxy --setup --gemini

This writes ~/.gemini/.env with GOOGLE_GEMINI_BASE_URL (http://127.0.0.1:8314/v1beta), GEMINI_MODEL, and disables telemetry, and selects api-key auth in ~/.gemini/settings.json to skip the first-launch prompt. Any user-set GEMINI_API_KEY is preserved. The Gemini surface is served at /v1beta/models/{model}:generateContent (plus streaming and token counting).

Tips