tengu_refusal_fallback_setting_changed
A Claude Code feature flag, read out of the shipped bundle. No mined inventory carries it: everything below comes from what this site has written about it.
The setting that switches models on a flagged refusal now records when you change it.
Not Anthropic's. This is the line from the earliest changelog entry here that named it, v2.1.251.
In the changelogs
4Releases whose published page names tengu_refusal_fallback_setting_changed.
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v2.1.270
Refusal-fallback "silent rearm" can now bypass the declined-route check for bio-category refusals
A new bypass lets Claude Code re-offer a fallback model for bio-related refusals even after the user already declined that route
gate cited by this entry, found in this entry's text
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v2.1.269
'Switch models on flag' setting changed from boolean toggle to an explicit choice
The 'switch models on flag' setting is now a named choice instead of a plain on/off toggle
gate cited by this entry
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v2.1.269
New telemetry event when user toggles the model-refusal-fallback auto-switch setting
Changing the automatic model-fallback-on-refusal setting now fires its own telemetry event and saves via userSettings
gate cited by this entry, found in this entry's text
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v2.1.251
Refusal-fallback model switching is now its own tracked setting
The setting that switches models on a flagged refusal now records when you change it.
gate cited by this entry, found in this entry's text
Gate readings
0No release here has a gate table behind it for this flag. Most published releases have none at all: the readings exist only for versions the pipeline captured flag state on.
First cited
2The earliest release whose published evidence quoted tengu_refusal_fallback_setting_changed was v2.1.251, 28 Aug 2026. That is the oldest release this project wrote about it, so it is a floor on the name's age and not the release that introduced it. It is not a presence reading: which builds carried the name is the table below.
Presence across releases
0The 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 feature flag does. All feature flags.