The Lab Notes

OpenAI

Codex adds a built-in Vertex AI provider and lists GPT-6.1 Terra

Codex CLI 0.165.0 adds a built-in Google Cloud Vertex AI provider, and 0.166.0 lists GPT-6.1 Terra in the Vertex AI and Amazon Bedrock catalogs.

The Lab Notes ·

A flat illustration of a grid of green and blue rounded panels, each with a slider slot and a black cable plugged in, on an orange background, with one larger green panel outlined in white at the center over a dark left half marked by faint concentric circles.

Codex now has a built-in Google Cloud Vertex AI provider, and its Vertex AI and Amazon Bedrock model catalogs list GPT-6.1 Terra. Developers who run Codex on Google Cloud can turn the provider on with one setting.

The provider arrived in Codex CLI 0.165.0 on Oct. 27, 2026, according to the OpenAI Codex changelog. Version 0.166.0 followed on Oct. 29 with the Terra listings for Vertex AI and Amazon Bedrock. The command-line tool installs through npm as @openai/codex.

Version 0.165.0 Adds the Provider and Terra

Codex CLI 0.165.0 added a built-in Vertex AI provider, configured with model_provider = "gcp". The same release added GPT-6.1 Terra to the model catalogs.

Reasoning effort can now change during a conversation by default for supported models. Memory v2 is on by default for fresh profiles, with support for importing memories from external agents. The session picker has a repository filter.

Codex also closed a marketplace URL validation gap. The gap could have allowed Git to connect to a different host than the one checked against allowed patterns.

Version 0.166.0 Puts Terra in the Provider Catalogs

Codex CLI 0.166.0 added GPT-6.1 Terra to the bundled, Vertex AI and Amazon Bedrock model catalogs.

The release also added codex doctor --network-only, which runs focused diagnostics on configuration, connectivity and WebSocket connections. It added codex queue --resume as well.

Our View

We think the setting model_provider = "gcp" matters because one value names the whole provider. Choosing where Codex sends its requests becomes a line in the configuration.

Developers on Google Cloud can set that line and have Codex use Vertex AI.

The catalog change adds a second step. The changelog lists Terra in the Vertex AI catalog from 0.166.0. For connection trouble, codex doctor --network-only runs focused diagnostics.

The benefit holds only if the Google Cloud project behind the provider can use Terra.