antigravity-sdk-e2e-dev

# Antigravity SDK harness: end-to-end dev & testing The `antigravity` harness drives Google's **Antigravity Python SDK** (`google-antigravity`, an in-process `Agent`/`Conversation`) and bridges Omnigent's `sys_*` tools into the SDK as `custom_tools`. It is **Gemini-native**: it authenticates with a Gemini / Antigravity API key (or Vertex AI) and has **no OpenAI-compatible gateway / Databricks path**. This skill is the proven recipe for running it **for real** against a live local server — not just the unit tests. > The harness runs as a **local runner** from your current checkout, so > `omni run <bundle> --server <url>` exercises exactly the code you're on. ## Prerequisites (check these first) 1. **You're on the branch you want to test.** The antigravity harness merged to `main` (#194). Test on `main` unless validating a specific branch. 2. **A Gemini API key is configured.** The SDK *requires* one (`AIza…`); there is no login flow. Verify (booleans only — never print the key): ```bash .venv/bin/python -c "from omnigent.onboarding.antigravity_auth import antigravity_api_key_configured as c; import os; print('config:', c(), 'env:', bool(os.environ.get('GEMINI_API_KEY') or os.environ.get('ANTIGRAVITY_API_KEY')))" ``` If both are `False`, run `omni setup` → **Antigravity** and paste a key, or `export GEMINI_API_KEY=AIza…`. 3. **`google-antigravity` is installed** (the `antigravity` extra — `pip install "omnigent[antigravity]"`): `.venv/bin/python -...