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codex is a replaceable harness lane inside Checkfu’s canonical product model. It is not another Agent type, deployment object, transcript, or policy authority.
First complete the hosted quickstart. It teaches the canonical Agent, Environment, Session, and event path without making a particular harness a prerequisite.
This flow runs from a Checkfu source checkout. Part of this flow is behind a rollout fence; a deployment that has not enabled it refuses the request rather than running it. Confirm capability status before making availability part of your application’s contract.

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Prepare and qualify the lane

Build the reviewed adapter image from the Checkfu source checkout:
Keep the immutable image digest printed by the command. Follow Bring a custom harness for the exact image, protocol, conformance, and evidence workflow. Low-level release and registration records are execution-lane artifacts only. They never replace the AgentVersion or Environment frozen by Session admission. Treat Codex session handles and adapter callbacks as lane-local implementation details. The Checkfu Session event log remains durable execution truth.

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Create the Agent and start a Session

Create or update the Agent through the current Agent operation. A material change creates the next immutable AgentVersion automatically; there is no separate Draft, Release, deployment, or publish lifecycle. Select the Environment separately when starting the Session:
Authenticated server context supplies durable actor attribution. Read settlement from the ordered Session event log rather than process exit, stream closure, or harness-native narration.

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Support boundary

Qualification applies to one exact immutable tuple. It does not make this lane a global default or prove every capability, provider, retention posture, or execution locus. Re-check capability status before using it in production.