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`CLAUDE_CODE_HANDBACK_PROVENANCE`

env never mined JSON

A Claude Code environment variable, read out of the shipped bundle. No mined inventory carries it: everything below comes from what this site has written about it.

Subagent reports can be wrapped so embedded instructions cannot pass as your commands, off here.

Not Anthropic's. This is the line from the earliest changelog entry here that named it, v2.1.242.

First seen — never in a mined build

Last seen — never in a mined build

Builds0 / 149on this box, as of v2.1.308

Written about v2.1.242 first named in a changelog, 24 Aug 2026

In the changelogs

Releases whose published page names CLAUDE_CODE_HANDBACK_PROVENANCE.

v2.1.277 18 Sep 2026
Handback provenance flag now defaults on
The setting controlling subagent report anti-injection wrapping now defaults to on

found in this entry's text
v2.1.277 18 Sep 2026
tengu_melodic_wolf fallback flips true
The tengu_melodic_wolf gate behind subagent report provenance now defaults to on if unset

found in this entry's text
v2.1.277 18 Sep 2026
CLAUDE_CODE_HANDBACK_PROVENANCE now defaults to enabled (tengu_melodic_wolf flipped to true)
The anti-injection wrapper for subagent reports (CLAUDE_CODE_HANDBACK_PROVENANCE) now defaults to on via the tengu_melodic_wolf gate

found in this entry's text
v2.1.242 24 Aug 2026
Subagent reports get an anti-injection wrapper, switched off in this build
Subagent reports can be wrapped so embedded instructions cannot pass as your commands, off here.

named in this entry, found in this entry's text

First cited

No release's published evidence quotes this name. The ledger indexes the Evidence lines of every changelog on this site, so this says nobody here has ever quoted it; it says nothing about how old the name is.

Presence across releases

The miner has never read a build containing this name. It is here because a changelog entry of ours names it, which is evidence that it existed and not evidence of which releases carried it. The inventory starts at v2.1.138 and everything older than that was never mined.

Read out of the published npm bundle release by release, and out of Anthropic's own documentation as this site captured it. Nothing on this page is a description anybody here wrote about what the environment variable does. All environment variables.

Names beside it

Every environment variable in the inventory starting claude_code, up to twelve of them.

CLAUDE_CODE_3P_PROBE_WROTE_HAIKU_DEFAULT v2.1.285
If your cloud account cannot use a model, Claude Code can step down to the next one; CLAUDE_CODE_DISABLE_MODEL_ACCESS_FALLBACK turns this off
CLAUDE_CODE_3P_PROBE_WROTE_OPUS_DEFAULT v2.1.207
Internal marker on third-party providers. When Claude Code itself writes ANTHROPIC_DEFAULT_OPUS_MODEL into its environment (the model availability probe on Bedrock, Vertex or Mantle, or a move down the model fallback ladder), it sets this variable to the same model ID. An ANTHROPIC_DEFAULT_OPUS_MODEL equal to it is treated as Claude Code's own choice rather than a user pin: it does not count as pinned, the probe does not skip it, and the fallback ladder may move it.
CLAUDE_CODE_3P_PROBE_WROTE_SONNET_DEFAULT v2.1.207
On third-party providers, Haiku model names are no longer skipped by the check that sets up the Sonnet default model
CLAUDE_CODE_3P_SEEDED_OPUS_DEFAULT v2.1.285
If your cloud account cannot use a model, Claude Code can step down to the next one; CLAUDE_CODE_DISABLE_MODEL_ACCESS_FALLBACK turns this off
CLAUDE_CODE_3P_SEEDED_SONNET_DEFAULT v2.1.285
If your cloud account cannot use a model, Claude Code can step down to the next one; CLAUDE_CODE_DISABLE_MODEL_ACCESS_FALLBACK turns this off
CLAUDE_CODE_ACCESSIBILITY v2.1.138
Set to 1 to keep the native terminal cursor visible and disable the inverted-text cursor indicator. Allows screen magnifiers like macOS Zoom to track cursor position
CLAUDE_CODE_ACCOUNT_TAGGED_ID v2.1.138
Overrides the user.account_id attribute Claude Code attaches to its OpenTelemetry data. It applies only when an account UUID is known and OTEL_METRICS_INCLUDE_ACCOUNT_UUID is not turned off (default on); when unset or empty, user.account_id is derived from the account UUID as a tagged ID of the form user_01....
CLAUDE_CODE_ACCOUNT_UUID v2.1.138
The device bridge is skipped entirely when the host's account UUID doesn't match the stored one.
CLAUDE_CODE_ACT_DONT_REDERIVE v2.1.162
Three existing feature gates moved position; their defaults are unchanged.
CLAUDE_CODE_ACTION v2.1.138
Marks a run as coming from the Claude Code GitHub Action. A truthy value (1, true, yes or on) makes Claude Code set CLAUDE_CODE_ENTRYPOINT to claude-code-github-action, but only when CLAUDE_CODE_ENTRYPOINT is not already set and the command is not claude mcp serve. It is also reported as isClaudeCodeAction in the environment details attached to telemetry.
CLAUDE_CODE_ADDITIONAL_DIRECTORIES_CLAUDE_MD v2.1.138
Set to 1 to load memory files from directories specified with --add-dir. Loads CLAUDE.md, .claude/CLAUDE.md, .claude/rules/*.md, and CLAUDE.local.md. By default, additional directories do not load memory files
CLAUDE_CODE_ADDITIONAL_PROTECTION v2.1.138
When truthy (1, true, yes or on), Claude Code adds the header x-anthropic-additional-protection: true to the default headers of the Anthropic API clients it creates.

Documentation pages 0

None of Anthropic's documentation pages this site has a copy of carries this name.