What is frontierfuse?

FrontierFuse is a tool that pairs a selectable frontier reasoning model with a separate coding executor model, so you can pick which AI gives advice and which one actually writes the code. It supports Codex, Claude, Grok, and Gemini as providers, and it treats the provider and the specific model as two separate choices rather than one, since a single provider can offer several different models. The project runs in two profiles. The advisor profile is executor led: the user works with the coding executor, which occasionally asks the frontier model for advice, then continues on its own. This uses fewer frontier model calls and is described as the best fit for most coding tasks. The orchestrator profile is host led: a host controller manages dispatched work through FrontierFuse and reviews it against a fixed verifier, which costs more coordination but suits multi step work that needs stronger checking before being marked done. The README is explicit that a plugin cannot swap out the underlying model already running the host coding tool, so the configured frontier model is a managed consultant rather than a replacement brain. Installation differs by host tool. In Claude Code, FrontierFuse installs through a plugin marketplace command, or manually by installing hooks if the marketplace is not used. For Codex, Grok Build, or Gemini CLI, it installs as a shared checkout cloned to a local folder, added to the shell's PATH, with a small MCP server registered so the host tool can call it. After installation, a diagnostics command called doctor checks whether the required provider command line tools are present, though it explicitly does not verify that your account is authenticated or entitled to use a given model, only that the command line tool itself exists. Configuration happens through a dedicated command line tool rather than by hand editing config files, and covers the profile, the frontier provider and model, the executor provider and model, an optional effort level for Codex and Grok, and how often FrontierFuse checks for updates.