Alpha· Notable · Confirmed

Thread history modes and managed session defaults arrive

Codex added per-thread history modes, managed new-thread model settings, and a standalone code-mode process host.

  • Feature
  • Agents
  • API
  • Sandbox

This prerelease gives applications more control over how thread history behaves and how new sessions inherit managed model settings, while code mode gains a separately supervised process host.

Alpha release context: 1 official tag was published that UTC day (rust-v0.143.0-alpha.26). The full comparison contains 35 commits and 267 changed files.

Evidence

App-server threads now expose a history mode.Why it matters: Clients can represent thread-history behavior explicitly instead of treating every thread as having the same history policy.

Direct evidence · Confirmed

Supporting sources

Conflicting sources

No conflicting sources recorded.

Managed model settings can be applied when a new thread is created.Why it matters: Administrators can shape new-session model defaults through managed configuration rather than relying only on each user's local choice.

Direct evidence · Confirmed

Supporting sources

Conflicting sources

No conflicting sources recorded.

Code mode gains a standalone process host.Why it matters: Code-mode execution can run through a dedicated host process with a clearer lifecycle boundary for supervision and recovery.

Direct evidence · Confirmed

Supporting sources

Conflicting sources

No conflicting sources recorded.

Availability

Availability note: these sources establish repository and CLI release activity. They do not, by themselves, prove that the same changes were live in Codex Desktop.

Availability by surface

SurfaceStatusClaim-level evidence
CLIPrerelease · Documented · General
  • claim-2026-06-26-thread-history-mode: Prerelease · Documented · General · version 0.143.0-alpha.26 · source-release-2026-06-26
  • claim-2026-06-26-managed-new-thread-model: Prerelease · Documented · General · version 0.143.0-alpha.26 · source-release-2026-06-26
  • claim-2026-06-26-standalone-code-mode-host: Prerelease · Documented · General · version 0.143.0-alpha.26 · source-release-2026-06-26
DesktopUnknown · Unknown · Unknown
IDEUnknownNo central-claim assertion recorded.
CloudUnknownNo central-claim assertion recorded.
MobileUnknownNo central-claim assertion recorded.