Source Intelligence
Sweep 28 Aug 2026 · 00:00Z Build v2.1.250 478 read Stable v2.1.236 Latest v2.1.250 Next v2.1.250 Feeds RSS JSON llms.txt

DisclaimerUnofficial, and not affiliated with Anthropic. Nearly all of this is read straight out of what ships: npm bundles, captured prompts, published docs. Anthropic's own notes go in verbatim, marked as theirs. The rest is my reading, and every entry carries the strings behind it. If one looks wrong, vote it down and say why.

Reference / Feature flags

tengu_tranquil_fern

A Claude Code feature flag, read out of the shipped bundle. It was in the build from v2.1.239 and was gone by v2.1.242.

What it is

Resuming a session that was in plan mode now puts you back in plan mode.

Not Anthropic's. This is the line from the earliest changelog entry here that named it, v2.1.239.

Presence across releases

ReleasesReadingDeclared typeDefault
2.1.245 – 2.1.250 5 releases never mined
2.1.242 – 2.1.243 2 releases not in the build
2.1.239 – 2.1.241 3 releases in the build unknown

A row reading never mined is a release with no archived bundle behind it. Nothing was read out of it, so nothing here says whether the name was in it. A declared type or a default is only ever what that release's own bundle stated.

Gate readings

No 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.

Changelog entries naming it

  1. v2.1.248Flag values can be pinned for the life of the process, and a new pinned flag appears

    Some feature flags now stay fixed for the whole session, including a new one that is on.

    gate cited by this entry

  2. v2.1.246Plan mode can be restored by reading the transcript

    Resuming a session can now re-enter plan mode by reading your transcript, and this is on by default.

    gate cited by this entry

  3. v2.1.239Resuming a session that was in plan mode puts you back in plan mode

    Resuming a session that was in plan mode now puts you back in plan mode.

    gate cited by this entry

Documentation pages

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

Names beside it

Every feature flag in the inventory starting tengu, up to twelve of them.

tengu_1p_event_batch_configNo description from anybody. never mined tengu_account_plugins_sync_enabledPlugins you enabled on claude.ai can be pulled to your machine, but only your account server can enable it. never mined tengu_account_skills_sync_enabledSyncing skills from your claude.ai account stays off, but its checks were reshaped for other synced resources too. 2.1.234 tengu_adopt_claimA stale session claim now keeps its entries, marked stale, instead of throwing them away. never mined tengu_adopt_linkAdopting an agent's transcript now hard-links the file, copying only when linking is impossible. never mined tengu_adopt_relinkOn startup, subagent transcripts stored as symlinks are converted to hard links or copies. never mined tengu_advisor_unknown_contentAdvisor output you couldn't see now shows an error or a clear "declined to advise" message. never mined tengu_agent_hooks_origin_untrustedAgents in untrusted folders can no longer define inline MCP servers; trust the project to allow it. never mined tengu_agent_list_attachNo description from anybody. 2.1.138 tengu_agent_proxy_download_queueDownload backlog on the agent proxy is now reported as a telemetry event. never mined tengu_agent_tool_selectedSDK result messages now include a summary of the subagents your session started. never mined tengu_agent_worktree_cwd_escape_blockedAgent commands now have a concrete worktree boundary, so escapes get blocked with a clearer log line. 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.