Sweep 19 Sep 2026 · 02:36Z Build v2.1.278 500 read Stable v2.1.267 Latest v2.1.278 Next v2.1.278 Feeds RSS JSON llms.txt Unofficial
Claude Code v2.1.274 ·

Background classifier gains a (currently dark) turn-brief tail-length knob

Background classifier gets a new, currently inactive setting to control how much recent conversation text it quotes

TierNothing to try yethow much it should matter to you
Useful3my rating, 1 to 5
Signal4worth watching, 1 to 5
AreaBackground Classifierwhat it touches
KindIn Developmentin v2.1.274,
Nothing to try yet No documentation found

Background classifier gets a new, currently inactive setting to control how much recent conversation text it quotes

What

Claude Code runs a background classifier behind the scenes to judge the state of a conversation turn. It has gained a new turnBriefTailChars setting that would control how many trailing characters of the turn's text get quoted when building a "turn brief" summary, replacing a fixed-length cutoff. When this setting is present, the classifier can also produce this new 'turn brief' output, using a larger token budget than before, and report it through a new turn_brief telemetry event alongside the existing background-classification events.

However, the function that would supply this setting is hard-coded to return nothing in this build, so the new behavior cannot actually take effect yet.

Why

This lays groundwork for a future feature that summarizes what happened at the end of a turn, but it has no effect on the current release.

Read from
Names in the bundleturnBriefTailChars
How sure we are
Something disagreesSomething we can check disagrees with this entry, or the writer said they could not settle it.
The writer flagged doubtWhether the tengu_bg_classifier_config or tengu_bg_classify gates are switched on for any account is unread, so nothing can be said about…

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