The auto-mode model selection logic now supports a modelByMainModel map in the tengu_auto_mode_config feature flag. This lets the server configure different auto-mode models depending on which primary model is currently active (including the [1m] extended-context variant), giving Anthropic more fine-grained control over model routing without a client update.
Evidence
Updated auto-mode resolver (search for "modelByMainModel")
Strings lifted out of the shipped bundle, so the claim above can be checked against them.
Feature flag
tengu_auto_mode_config Not enough to sayNothing here resolved what this flag was doing on this version, so nothing here should be read as on or off.
This account: no value returned · anonymous baseline: no value returned · compiled default in v2.1.166: not a boolean we can read
These values were read against a different version of Claude Code, so treat them as the nearest reading available instead of one taken on this release.
Read once, for one account on one subscription tier, against v2.1.166. It isn't a statement about your account. What a flag value here can and cannot tell you
Flag reading moved
The flag server now returns {"editRemovalCap":3000,"editRemovalVisibility":true,"enabled":"enabled","envOnboarding":true,"gitStatusType":true,"gitStatusUploads":false,"jsonlTranscript":true,"outcomeVisibility":false,"repoVisibility":true,"sameTurnSiblingContext":true,"severityByModel":{"claude-opus-4-8":{"t1":45,"t2":35},"claude-opus-4-8[1m]":{"t1":45,"t2":35},"claude-sonnet-5":{"t1":25,"t2":35},"claude-sonnet-5[1m]":{"t1":25,"t2":35}},"severityBySite":{"compactFabCheck":"on","handoff":"on","investigator":"on","sandboxNetwork":"on","workflowGate":"on"},"twoStageClassifier":true} for tengu_auto_mode_config, read as this account.
A reading is one sample. Claude Code evaluates its flags remotely, so no client sees the targeting rule behind a value and this says nothing about your account.
Flag reading moved
The flag server now returns {"editRemovalCap":3000,"editRemovalVisibility":true,"enabled":"enabled","envOnboarding":true,"gitStatusType":true,"gitStatusUploads":false,"jsonlTranscript":true,"modelByMainModel":{"claude-haiku-5-5":"claude-sonnet-5[1m]","claude-haiku-5-5[1m]":"claude-sonnet-5[1m]"},"outcomeVisibility":false,"repoVisibility":true,"sameTurnSiblingContext":true,"severityByModel":{"claude-opus-4-8":{"t1":45,"t2":35},"claude-opus-4-8[1m]":{"t1":45,"t2":35},"claude-sonnet-5":{"t1":25,"t2":35},"claude-sonnet-5[1m]":{"t1":25,"t2":35}},"severityBySite":{"compactFabCheck":"on","handoff":"on","investigator":"on","sandboxNetwork":"on","workflowGate":"on"},"twoStageClassifier":true} for tengu_auto_mode_config, read as this account.
A reading is one sample. Claude Code evaluates its flags remotely, so no client sees the targeting rule behind a value and this says nothing about your account.
Flag reading moved
The flag server now returns {"editRemovalCap":3000,"editRemovalVisibility":true,"enabled":"enabled","envOnboarding":true,"gitStatusType":true,"gitStatusUploads":false,"jsonlTranscript":true,"outcomeVisibility":false,"repoVisibility":true,"sameTurnSiblingContext":true,"severityByModel":{"claude-opus-4-8":{"t1":45,"t2":35},"claude-opus-4-8[1m]":{"t1":45,"t2":35},"claude-sonnet-5":{"t1":25,"t2":35},"claude-sonnet-5[1m]":{"t1":25,"t2":35}},"severityBySite":{"compactFabCheck":"on","handoff":"on","investigator":"on","sandboxNetwork":"on","workflowGate":"on"},"twoStageClassifier":true} for tengu_auto_mode_config, read as this account.
A reading is one sample. Claude Code evaluates its flags remotely, so no client sees the targeting rule behind a value and this says nothing about your account.
Flag reading moved
The flag server now returns {"editRemovalCap":3000,"editRemovalVisibility":true,"enabled":"enabled","envOnboarding":true,"gitStatusType":true,"gitStatusUploads":false,"jsonlTranscript":true,"modelByMainModel":{"claude-haiku-5-5":"claude-sonnet-5[1m]","claude-haiku-5-5[1m]":"claude-sonnet-5[1m]"},"outcomeVisibility":false,"repoVisibility":true,"sameTurnSiblingContext":true,"severityByModel":{"claude-opus-4-8":{"t1":45,"t2":35},"claude-opus-4-8[1m]":{"t1":45,"t2":35},"claude-sonnet-5":{"t1":25,"t2":35},"claude-sonnet-5[1m]":{"t1":25,"t2":35}},"severityBySite":{"compactFabCheck":"on","handoff":"on","investigator":"on","sandboxNetwork":"on","workflowGate":"on"},"twoStageClassifier":true} for tengu_auto_mode_config, read as this account.
A reading is one sample. Claude Code evaluates its flags remotely, so no client sees the targeting rule behind a value and this says nothing about your account.
Flag reading moved
The flag server now returns {"editRemovalCap":3000,"editRemovalVisibility":true,"enabled":"enabled","envOnboarding":true,"gitStatusType":true,"gitStatusUploads":false,"jsonlTranscript":true,"outcomeVisibility":false,"repoVisibility":true,"sameTurnSiblingContext":true,"severityByModel":{"claude-opus-4-8":{"t1":45,"t2":35},"claude-opus-4-8[1m]":{"t1":45,"t2":35},"claude-sonnet-5":{"t1":25,"t2":35},"claude-sonnet-5[1m]":{"t1":25,"t2":35}},"severityBySite":{"compactFabCheck":"on","handoff":"on","investigator":"on","sandboxNetwork":"on","workflowGate":"on"},"twoStageClassifier":true} for tengu_auto_mode_config, read as this account.
A reading is one sample. Claude Code evaluates its flags remotely, so no client sees the targeting rule behind a value and this says nothing about your account.
Flag reading moved
The flag server now returns {"editRemovalCap":3000,"editRemovalVisibility":true,"enabled":"enabled","envOnboarding":true,"gitStatusType":true,"gitStatusUploads":false,"jsonlTranscript":true,"modelByMainModel":{"claude-haiku-5-5":"claude-sonnet-5[1m]","claude-haiku-5-5[1m]":"claude-sonnet-5[1m]"},"outcomeVisibility":false,"repoVisibility":true,"sameTurnSiblingContext":true,"severityByModel":{"claude-opus-4-8":{"t1":45,"t2":35},"claude-opus-4-8[1m]":{"t1":45,"t2":35},"claude-sonnet-5":{"t1":25,"t2":35},"claude-sonnet-5[1m]":{"t1":25,"t2":35}},"severityBySite":{"compactFabCheck":"on","handoff":"on","investigator":"on","sandboxNetwork":"on","workflowGate":"on"},"twoStageClassifier":true} for tengu_auto_mode_config, read as this account.
A reading is one sample. Claude Code evaluates its flags remotely, so no client sees the targeting rule behind a value and this says nothing about your account.
Flag reading moved
The flag server now returns {"editRemovalCap":3000,"editRemovalVisibility":true,"enabled":"enabled","envOnboarding":true,"gitStatusType":true,"gitStatusUploads":false,"jsonlTranscript":true,"outcomeVisibility":false,"repoVisibility":true,"sameTurnSiblingContext":true,"severityByModel":{"claude-opus-4-8":{"t1":45,"t2":35},"claude-opus-4-8[1m]":{"t1":45,"t2":35},"claude-sonnet-5":{"t1":25,"t2":35},"claude-sonnet-5[1m]":{"t1":25,"t2":35}},"severityBySite":{"compactFabCheck":"on","handoff":"on","investigator":"on","sandboxNetwork":"on","workflowGate":"on"},"twoStageClassifier":true} for tengu_auto_mode_config, read as this account.
A reading is one sample. Claude Code evaluates its flags remotely, so no client sees the targeting rule behind a value and this says nothing about your account.
Flag reading moved
The flag server now returns {"editRemovalCap":3000,"editRemovalVisibility":true,"enabled":"enabled","envOnboarding":true,"gitStatusType":true,"gitStatusUploads":false,"jsonlTranscript":true,"modelByMainModel":{"claude-haiku-5-5":"claude-sonnet-5[1m]","claude-haiku-5-5[1m]":"claude-sonnet-5[1m]"},"outcomeVisibility":false,"repoVisibility":true,"sameTurnSiblingContext":true,"severityByModel":{"claude-opus-4-8":{"t1":45,"t2":35},"claude-opus-4-8[1m]":{"t1":45,"t2":35},"claude-sonnet-5":{"t1":25,"t2":35},"claude-sonnet-5[1m]":{"t1":25,"t2":35}},"severityBySite":{"compactFabCheck":"on","handoff":"on","investigator":"on","sandboxNetwork":"on","workflowGate":"on"},"twoStageClassifier":true} for tengu_auto_mode_config, read as this account.
A reading is one sample. Claude Code evaluates its flags remotely, so no client sees the targeting rule behind a value and this says nothing about your account.