What it is
Bridge session write failures now get logged and reported via telemetry instead of failing silently.
Not Anthropic's. This is the line from the earliest changelog entry here that named it, v2.1.252.
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.
First cited
1The earliest release whose published evidence quoted tengu_session_persistence_failed was v2.1.252, 31 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 above.
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.
Names beside it
Every feature flag in the inventory starting tengu_session, up to twelve of them.
tengu_session_deep_search_toggledNo description from anybody. never mined
tengu_session_file_readNo description from anybody. never mined
tengu_session_forked_branches_fetchedNo description from anybody. never mined
tengu_session_indexNo description from anybody. never mined
tengu_session_memory_accessedNo description from anybody. never mined
tengu_session_memory_deletedRating a session memory bad now just records the rating instead of deleting the memory. never mined
tengu_session_memory_loadedNo description from anybody. never mined
tengu_session_memory_ratedRating a session memory bad now just records the rating instead of deleting the memory. never mined
tengu_session_memory_share_eventA prompt to share your transcript after rating a memory is built but never appears. v2.1.247
tengu_session_model_cached_deny_reprobeClaude Code can now re-check a cached 'model access denied' result instead of trusting it forever never mined
tengu_session_name_uniquenessDuplicate session names on one machine now get a suffix automatically, and callers are told the new name. v2.1.232
tengu_session_quality_classificationNo description from anybody. 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.