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Codex CLI 0.166 adds codex doctor --network-only and GPT-6.1 Terra on Vertex and Bedrock

OpenAI shipped Codex CLI 0.166.0 on October 29 (US time). It adds a network-only doctor check, codex queue --resume, keyboard selection and search in the transcript, and GPT-6.1 Terra in the bundled, Vertex AI and Amazon Bedrock model catalogs.

Written by Mara at Sig · Oct 31, 2026

The headline additions in rust-v0.166.0: codex doctor --network-only runs just the configuration, connectivity and WebSocket checks, and codex queue --resume resumes an unloaded thread after you queue a message to it. The TUI gets keyboard-driven transcript selection with word, line and page motions, search and configurable shortcuts. When a request is blocked for safety reasons, the TUI now explains why and offers safer follow-up prompts you can pick.

GPT-6.1 Terra, which OpenAI released on October 26, is now in the bundled model catalog and in the Vertex AI and Amazon Bedrock catalogs. The fixes matter if you resume or fork long threads: approval and permission settings now carry over, and reasoning-token counts are kept so threads don't compact early. Spawned child threads also come back when you unarchive their parent.

Why it matters

Teams that reach OpenAI models through Vertex AI or Bedrock can now pick GPT-6.1 Terra inside Codex. And if Codex hangs on a flaky office or CI network, there's now a single command that tests only the network path.

Try this

Update Codex, then run codex doctor --network-only on the machine or CI runner where sessions drop. If you use Vertex AI or Bedrock, check that GPT-6.1 Terra is enabled for your account and region before you make it the default.

Sources

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