Source Intelligence

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.

All of v2.1.251 Home All releases olderv2.1.250
Claude Code v2.1.251

Off-by-default artifact frame relay bypass

Not switched on
Useful1 Signal3
Artifacts

An alternate way of serving artifact content exists but is unreachable in normal use.

A frame-relay bypass sits behind a remote flag defaulting false plus remote-session and bot-context conditions.

Feature flag
tengu_cobalt_plinth_linden Off in both readings

The flag server returned off for the account this site reads and for the anonymous baseline. A reading of off cannot rule out a rollout these two readings sit outside of.

This account: off · anonymous baseline: off · compiled default in v2.1.251: not a boolean we can read

Read once, for one account on one subscription tier, against v2.1.251. It isn't a statement about your account. What a flag value here can and cannot tell you

What

A new flag, tengu_cobalt_plinth_linden, controls an extra path for serving artifact content that bypasses the usual frame relay. It defaults to false and additionally needs a remote Claude Code session and an internal bot-context marker, so nothing in normal use reaches it.

Evidence

tengu_cobalt_plinth_linden

Strings lifted out of the shipped bundle, so the claim above can be checked against them.

See this entry in the whole of v2.1.251 →