[Apeksha9389]

Deleting a default language context removes its live connection but leaves its id in default_websockets. The next run_code(..., language="python") resolves that stale id and returns HTTP 404 instead of creating a replacement. Executions without a language also need the same default-resolution path.

Route implicit Python execution through the existing per-language lock and recreate a default when its cached id is absent from the live context registry. Refresh the Python default alias when creating its replacement. Explicit context ids retain their existing lookup and 404 behavior. Includes a template patch changeset.

Validation on Python 3.12:

• The explicit-language deletion regression fails on unchanged main with 404 Not Found: Context None not found.
• Ten selected HTTP-level context tests pass against a local Python-only template server backed by a real Jupyter kernel over a Unix socket. They cover both deletion forms, default and non-default restart, context independence, invalid arguments and unknown ids. The explicit-language regression also passes on a fresh local server.
• Ruff 0.11.13 check and format pass on both changed Python files.

No cloud sandbox, other language kernels, or full integration-suite run was performed. The added tests use the existing CodeInterpreter harness and standard client fixture, so they also run in the repository's sandbox test setup.

Prepared with AI assistance; reproduced and tested locally.

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[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-10-20T11:43:51.868665Z	cf5471f	PR opened

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[Apeksha9389]

@cla-bot check

[cla-bot]

The cla-bot has been summoned, and re-checked this pull request!

[mishushakov]

Hey, appreciate the PR here, but it has to be done differently.

[Apeksha9389]

Thanks for reviewing. Could you clarify the intended behavior after a default language context is deleted, and which part of this approach should change?