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OpenRelay is in early access, and the /v1 API is stable. New capabilities ship in the changelog.
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GuidesInference APIs

Codex CLI

Point the OpenAI Codex CLI at OpenRelay through the Responses endpoint, with a config.toml provider block and an OpenRelay API key.

Codex talks to models through the Responses endpoint. Add OpenRelay as a model provider in ~/.codex/config.toml:

model = "openrelay/<model>"
model_provider = "openrelay"

[model_providers.openrelay]
name = "OpenRelay"
base_url = "https://inference.openrelay.inc/v1"
env_key = "OPENRELAY_API_KEY"
wire_api = "responses"

Then export your API key and run Codex:

export OPENRELAY_API_KEY=or_...
codex

Use a model whose supported_apis lists responses (see GET /v1/models). Copy-ready config for each model is on its page in the dashboard, under the Responses tab.

What to expect

  • Conversation state. Codex sends the whole conversation on every turn with store: false, which is how OpenRelay serves Responses.
  • Prefix caching. Codex sends its session id as prompt_cache_key, which OpenRelay passes to the model. A later turn that lands on a replica holding its prefix reuses the cache. Only the cached tokens the model reports bill at the cached-input rate.
  • Web search. Codex can send the hosted web_search tool. OpenRelay removes it, and the model works without search.
  • Shell and patch tools. These are client tools: the model emits the call and Codex runs it on your machine.
  • Context. A Codex session starts near 9,000 tokens of instructions and tools, so it needs the 32,768-token or larger window every Responses model has.

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