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Gemini

Configure Gemini in Happier, including model selection and ACP-backed behavior.

Happier integrates Gemini through the local Gemini CLI/runtime and ACP-compatible messaging.

Gemini is an experimental integration. It works and people use it daily, but its surface is younger than Claude, Codex or OpenCode and is more likely to change. What it supports today is in Agent capabilities.

Requirements

  • Gemini CLI installed on your machine.
  • CLI available on PATH (or set HAPPIER_GEMINI_PATH if needed).

Install Gemini

Happier can install it for you:

happier install provider gemini
gemini --version

Or install manually:

npm install -g @google/gemini-cli
gemini --version

Local authentication in Happier

Gemini supports machine-local auth management in:

  • Settings → AI & Agents → AI backends → Gemini

From there you can:

  • check Gemini’s local auth state on the selected machine
  • open Gemini’s native CLI auth flow directly inside Happier
  • refresh the auth state with Check now

Happier can detect Gemini auth from environment variables, local Gemini auth/config files, and supported Google ADC files.

For the shared user guide, see Provider authentication.

Start Gemini with Happier

happier gemini

Authentication (connected services)

Gemini auth is managed through Happier connected services (gemini):

  • Settings → Connected services → Gemini
  • Or CLI: happier connect gemini

For paste/redirect flows, Happier exchanges the OAuth code on the server and returns an encrypted bundle to the client (no Gemini OAuth secrets are bundled into the app UI).

Supported UI methods:

  • paste redirect URL
  • in-app browser on native

On web, Happier uses the paste flow.

If you are self-hosting and need to override OAuth client settings, see:

Model selection

Model selection is capability-driven and can be set from:

  • CLI start options
  • App session input settings (when exposed for the current runtime)

For cross-provider model behavior, live model lists, and favorites, see Model and engine selection.

Troubleshooting

  • If Gemini is not detected, verify CLI installation and restart Happier.
  • If needed, point to binary explicitly with HAPPIER_GEMINI_PATH.

OpenCode

Configure OpenCode in Happier, including the default server-native backend, app ↔ terminal control switching, and attach behavior.

Grok Build (experimental)

Configure the Grok Build CLI in Happier, including authentication, steering, resume, activity, and current ACP limitations.

On this page

RequirementsInstall GeminiLocal authentication in HappierStart Gemini with HappierAuthentication (connected services)Model selectionTroubleshootingRelated