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 v2.1.267 ·

Artifact hot-update mechanism gets its own flag and deadline/seq schema fields

Artifact hot-update/live-doc syncing now has its own feature flag and new deadline, seq, and unchanged fields

TierNothing to try yethow much it should matter to you
Useful3my rating, 1 to 5
Signal3worth watching, 1 to 5
AreaArtifactswhat it touches
KindIn Developmentin v2.1.267,
Group of 3 Nothing to try yet

Artifact hot-update/live-doc syncing now has its own feature flag and new deadline, seq, and unchanged fields

What

  • The artifact hot-update (live-reload) check now uses its own CLAUDE_CODE_ARTIFACT_HOT environment variable and tengu_copper_hinge_wren gate, instead of incorrectly sharing the CLAUDE_CODE_ARTIFACT_TYPES variable and tengu_cobalt_plinth_larch gate used by the separate artifact-types feature.
  • Artifact publish requests can now pass a deadline field, which is forwarded to the create/update/live-doc publish calls; the publish response can echo back deadline plus a deadlineDropped flag, along with new seq and unchanged fields.
  • The artifact/live-doc read response schema gains seq and unchanged fields, and (only when a feature gate is on) deadline/deadlineDropped fields, supporting a long-poll style read.

Why

Separating the hot-update flag from the unrelated artifact-types flag means each can be turned on or off independently without accidental interference. The new deadline/seq/unchanged fields lay the groundwork for telling older open copies of a published artifact when to stop and for tracking whether a read actually changed.

Read from
Names in the bundledeadline
Since it was published

The entry above is what we published on the day. These lines were added later, as Anthropic's own pages caught up, and they sit beside the original rather than replacing it.

Added since A small documentation edit on Environment variables touched a line naming deadline after this was published. | `CLAUDE_CODE_WEBFETCH_DEADLINE_MS` | Upper bound in milliseconds on how long [WebFetch](/docs/en/tools-reference#webfetch-tool-behavior) waits for a page to download, including any redirects it follows. A download that hasn't completed b… env-vars see the edit
Confirmed since Anthropic's documentation has since written up deadline, on Claude Code changelog. * Fixed WebFetch hanging indefinitely on a server that keeps the response open without finishing; a fetch now fails after 300 seconds. Set `CLAUDE_CODE_WEBFETCH_DEADLINE_MS` to override the deadline (0 turns it off) changelog see the edit
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 doubtThe finding does not say what the deadline value controls in practice or when `deadlineDropped` would be set.
Anthropic's documentation agreesAnthropic's documentation has since written up deadline, on Claude Code changelog.

See this entry in the whole of v2.1.267 →