Claude Code for $0? Use OmniRoute

OmniRoute is a gateway you run locally. It puts one endpoint in front of a lot of model providers, several of which are free and need no signup — and Claude Code takes its base URL from config, so you point it at the gateway instead of at Anthropic. That is where the $0 comes from: not a discount, a different model answering.

Every value below is from OmniRoute’s own README and docs/guides/CLAUDE-CODE-CONFIGURATION.md. Where a write-up I found disagrees, I say so and why it matters.

Prerequisites

node -v            # 22.x, 24 LTS (recommended), 25.x or 26.x
claude --version   # npm i -g @anthropic-ai/claude-code

1. Install and start

npm install -g omniroute
omniroute

Dashboard	http://localhost:20128
API endpoint	http://localhost:20128/v1

A fresh install has keyless providers already wired — OpenCode Free, Kilo Code, Pollinations — so there is nothing to sign up for, and the pseudo-model auto routes to whichever of them is available.

2. Create your gateway key

The gateway authenticates its own endpoint, so you need a key before Claude Code can talk to it.

Dashboard → Endpoints → generate. Copy it; it looks like oma_live_….

3. Configure Claude Code

Add this to ~/.claude/settings.json. Four lines, and none of them names a model — auto is the default, and on a keyless install that is the whole point:

{
  "env": {
    "ANTHROPIC_BASE_URL": "http://localhost:20128",
    "ANTHROPIC_AUTH_TOKEN": "oma_live_xxx",
    "CLAUDE_CODE_DISABLE_NONESSENTIAL_TRAFFIC": "1",
    "CLAUDE_CODE_ENABLE_GATEWAY_MODEL_DISCOVERY": "1"
  }
}

The last line lets Claude Code list the gateway’s models in its own picker rather than Anthropic’s. Claude Code reads env once, at startup — restart it.

Pinning specific models, optionally

To bind Claude Code’s Opus/Sonnet/Haiku tiers to particular models, add three more. Use IDs from a provider you actually have — the free ones are prefixed oc/, and pasting a glm/ or kmc/ ID from a guide will fail with a 401 because those are paid providers you have not connected:

{
  "env": {
    "ANTHROPIC_DEFAULT_OPUS_MODEL": "oc/deepseek-v4-flash-free",
    "ANTHROPIC_DEFAULT_SONNET_MODEL": "oc/deepseek-v4-flash-free",
    "ANTHROPIC_DEFAULT_HAIKU_MODEL": "oc/deepseek-v4-flash-free"
  }
}

Model IDs move. Take the exact strings from your dashboard’s model list, not from here.

4. Verify the endpoint

curl http://localhost:20128/v1/models \
  -H "Authorization: Bearer oma_live_xxx"

A JSON list means the endpoint and the key are both good. It is also where you read the real model IDs for the optional block above.

5. Prove it is actually routing

That only proves the gateway is up. It does not prove Claude Code is using it, and the failure mode above is silent. Two checks that cannot lie:

1. Run /status in Claude Code. The API base URL should read localhost:20128, not api.anthropic.com.
2. Stop the gateway — Ctrl-C in the omniroute terminal — and send a prompt. Claude Code should fail to connect. Start it again; the prompt works.

If step 2 answers normally with the gateway down, you are still on Anthropic’s API and still being billed.

If something breaks

Symptom	Cause
Works, but still billed	/v1 left on the base URL, or Claude Code not restarted
400 Ambiguous model	Use a prefixed ID, e.g. cc/claude-opus-4-8
401 on a specific model	That provider is not connected — pick one from /v1/models
401 from the gateway	Key missing or not the one from Dashboard → Endpoints
Connection refused	omniroute is not running, or something took port 20128