Cheaper is a gateway that speaks two protocols — the Anthropic Messages API and the OpenAI-compatible Chat Completions API — so any tool that lets you set a custom base URL can route through it and get cheaper-by-default model selection.
The rule of thumb: start the gateway, then point a tool's base URL (or "custom endpoint") setting at it using the matching protocol below. Your own API key still flows straight through to the provider.
cheaper gateway startSet this environment variable, then run the tool as usual:
export ANTHROPIC_BASE_URL=http://localhost:8787Point the tool's OpenAI base URL setting at this value (some tools read it from an
OPENAI_BASE_URL-style variable instead — check the tool's own docs for where it goes):
http://localhost:8787/v1Coverage depends on the tool, not on Cheaper:
| Situation | Result |
|---|---|
| Tool lets you set an Anthropic or OpenAI base URL | Fully routed + monitored |
| Tool speaks a native, non-OpenAI protocol (e.g. Google Gemini) with no compat mode | Needs a protocol adapter (planned) |
| Tool hard-codes its endpoint with no custom base URL | Not routable by any proxy |
Tool names are the vendors' marks, listed to show interoperability. Exact settings (env var vs. config file) differ per tool — check each tool's own docs for where to set the base URL. Where a tool only speaks a provider protocol Cheaper doesn't yet translate, an adapter is on the roadmap; the Anthropic and OpenAI-compatible front-ends ship today.