Source Intelligence
Sweep 28 Aug 2026 ยท 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_slate_anchor

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.

What it is

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

Not Anthropic's. This is the line from the earliest changelog entry here that named it, v2.1.248.

Presence across releases

The 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.

Gate readings

ReleaseResolvedThis accountAnonymousCompiled default
v2.1.248 Gate removed from the code on on not a boolean we can read

Two arms, because they disagree: this account is the one account this site reads and anonymous is a baseline with no identity attached. A reading says nothing about your account, and off cannot rule out a rollout both readings sit outside of. What these readings can and cannot show.

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

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_slate, up to twelve of them.

tengu_slate_fernNo description from anybody. 2.1.172 tengu_slate_finchNo description from anybody. 2.1.138 tengu_slate_harborREPL contexts moved to a registry that releases timers even on error paths. 2.1.138 tengu_slate_harbor_experimentNo description from anybody. 2.1.138 tengu_slate_harrierClaude no longer spends up to a minute investigating before asking you a clarifying question. 2.1.138 tengu_slate_heronNo description from anybody. never mined tengu_slate_ibisExplore and plan agents are now always on unless you set the disable environment variable yourself. 2.1.217 tengu_slate_kestrelNo description from anybody. 2.1.138 tengu_slate_lanternA new --watch-artifact flag follows a claude.ai artifact for new versions and comments, but needs account access. 2.1.198 tengu_slate_lantern_emberRe-armed artifact watches could reuse an existing connection instead of starting over, but the flag is off. 2.1.236 tengu_slate_meadowNo description from anybody. 2.1.138 tengu_slate_mothNo description from anybody. 2.1.191

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.