New env vars added to the passthrough allowlist

Three new env vars are preserved and passed through to subprocesses and sandboxes.

You'll notice Notable No documentation found Improvements

JSON All of v2.1.257

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3Signal: worth watching, 1 to 5

EnvironmentArea: what it touches

ImprovementsKind: in v2.1.257, 01 Sep 26

What probably matters to youSection of the release

CLAUDE_CODE_CCR_SURFACE, CLAUDE_CODE_MODEL_CATALOG_URL, and CLAUDE_CODE_ARTIFACT_OPEN_ACTION are now included in the set of environment variables Claude Code preserves and passes through, for example to subprocesses or sandboxes.

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One source agreesOne thing we can check says the same as this entry.

The name it cites is new in this buildNew in this build: CLAUDE_CODE_ARTIFACT_OPEN_ACTION

The build it came inv2.1.257

1 Sep 2026 · 505 entries, this one is #122.

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Names in this entry

envCLAUDE_CODE_CCR_SURFACE
Setting CLAUDE_CODE_CCR_SURFACE=tag adds a hidden claude-tag-plugins marketplace to plugin search and download.
envCLAUDE_CODE_MODEL_CATALOG_URL
The model list, aliases and defaults can now come from a signed remote catalog document rather than only from app releases.
envCLAUDE_CODE_ARTIFACT_OPEN_ACTION
Whether an artifact auto-opens in a local browser is now behind a new env var, off by default.

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