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Gluon

Codex

Codex (the codex binary) is OpenAI’s harness. It is strong at well-specified implementation work and careful, test-driven changes. Gluon’s intake agent can also run on your ChatGPT plan through codex app-server.

Vendor docs: Codex CLI.

Connections

Section titled “Connections”
Connection Supported
Subscription ChatGPT plan, personal use. Gluon offers codex login.
API key OpenAI
Amazon Bedrock Yes
OpenRouter Yes

On an OpenAI key Codex gets a model provider of its own that reads the key, because its built-in one prefers the ChatGPT login. That provider points at OpenAI’s own API endpoint. It is the one base URL Gluon sets besides OpenRouter’s, and only on this API-key connection. On Bedrock, Codex reaches the models through its own Bedrock provider. See Connections.

How Gluon launches it

Section titled “How Gluon launches it”

Gluon starts codex in its own pseudo-terminal with the model, the effort and the spec, which follows --. For hooks Gluon passes one setting per event on the command line and writes nothing anywhere.

Codex asks once for a “Hooks need review” approval of those hooks. The set is always the same bytes, so you review it once and not again until Gluon changes it on purpose.

Codex reads AGENTS.md itself. Gluon tells it to read CLAUDE.md or GEMINI.md when your repository has one.

Modes

Section titled “Modes”
  • explore starts it in its read-only sandbox, with approvals set to never.
  • plan has no flag in Codex, so Gluon types /plan into it once it is up. It works only in Gluon’s frame: a direct launch from the command line and a terminal without a pseudo-terminal refuse it.

See Modes.

Sessions, cost and context

Section titled “Sessions, cost and context”
  • Resume. Codex makes its own session id, which its hook sends back to Gluon. Without a pseudo-terminal Gluon never sees the id, so that session cannot be resumed.
  • Cost. From Codex’s OpenTelemetry logs, priced at the table’s price. An estimate (~$): Codex never reports the service tier that was served, so Gluon assumes the one requested.
  • Context. From the main conversation’s last response, over the model’s window.

See Cost and context.

Quirks

Section titled “Quirks”
  • Codex uses ctrl+] itself, so don’t set that as Gluon’s home key for it (the config reference has the key and its default).
  • A ChatGPT account may refuse some models. gluon doctor shows Codex’s refusal and routing moves on.
  • A newer Codex can break the intake agent route on the ChatGPT plan, because that route is fail-closed on features Gluon has not checked. gluon doctor shows it.

Next steps

Section titled “Next steps”
  • Connections: compare a plan, a key, Bedrock and OpenRouter.
  • Modes: why Codex’s plan mode needs Gluon’s frame.
  • Antigravity: the next agent.