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NousResearch/hermes-agent

gpt-5.3-codex model unsupported or removed from Codex catalog

Cluster 52492 · agent. Data as of

Nothing open on GitHub. Fix merged in #115879 on 19 Sep 2026. Check it covers your case.

The short answer

0open issues
0open PRs
3items grouped
Known?
Yes. 3 related items grouped here, 1 issue already closed.
Fix event
A fix was merged to main in PR #115879. Check it covers your case. No release data is tracked.
Tracker
The maintainers' tracker marks this resolved, deciding PR #115879. That is separate from the fix event.
Still open
Nothing open on GitHub.

One bug report describes a 400 error saying 'gpt-5.3-codex' is not supported when using Codex. Two pull requests propose removing that model from the Codex catalog and the curated fallback list, apparently because it is retired; their outcome is not established here.

Open issues0

No open issues.

Open PRs0

No open pull requests.

Fixes on record

Merged to main. A stamp counts the issues a fix is linked to.

  • #115879 fix(codex): retired gpt-5.3-codex no longer offered in the Codex model catalog (#52492, salvage #52509)

    merged to main

    files: hermes_cli/cli_model_switch_mixin.py, hermes_cli/codex_models.py, run_agent.py, tests/agent/test_codex_silent_hang_hint.py, tests/agent/test_codex_ttfb_watchdog.py, tests/hermes_cli/test_codex_models.py, website/docs/user-guide/configuration.md, website/docs/user-guide/features/fallback-providers.md, website/i18n/zh-Hans/docusaurus-plugin-content-docs/current/user-guide/configuration.md, website/i18n/zh-Hans/docusaurus-plugin-content-docs/current/user-guide/features/fallback-providers.md

1 PR closed without merging

From the close comments: merged via another change 1

  • #52509 fix(codex): remove dead gpt-5.3-codex from curated fallback list (#52492) · merged via another change → 3934fe5, #115879, #52492, #52509
Closed issues · 1
  • Closed#52492[Bug]:400 - 'gpt-5.3-codex' model is not supported when using Codex
How this cluster was grouped
  • Link evidence (structural links throughout): every member is connected by structural evidence: shared changed files, or a closing/superseded reference.
  • Pairwise link density 0.67: the share of item pairs that carry a link, counting a structural link in full and a relevance-only link at 0.36. 1.00 means every pair is linked.

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At a glance

Subsystem
agent
Merged PRs
#115879
Closed issues
1
Attempts
1 PR closed without merging
Fix link checked
19 Sep 2026

For your agent

The same facts, typed.

cluster/52492.json
cluster/52492.md