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 v2.1.275 ·

Stalled background subagents can now be 'parked' instead of aborted

A stalled async subagent can now be parked with a partial result instead of always being aborted

TierNothing to try yethow much it should matter to you
Useful3my rating, 1 to 5
Signal3worth watching, 1 to 5
AreaSubagentswhat it touches
KindIn Developmentin v2.1.275,
Group of 2 Nothing to try yet

A stalled async subagent can now be parked with a partial result instead of always being aborted

What

  • When an async (background) subagent's stall watchdog fires, and the subagent has produced at least one assistant message, the run can now be marked "parked" instead of always being hard-aborted with a "stall watchdog fired" error.
  • Parking synthesizes a completion from the transcript produced so far, injects a message, clears any in-flight tool-use IDs, and finalizes the run with a summary and usage info.
  • This behavior is gated behind an internal flag (tengu_zinc_harbor) and emits a subagent_park telemetry event.

Why Previously a stalled background subagent always failed outright, discarding any partial progress. Parking preserves whatever work the subagent already did instead of throwing it away.

Read from
Feature flag
tengu_zinc_harbor 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 v2.1.275: off

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 v2.1.275. It isn't a statement about your account. What a flag value here can and cannot tell you

How sure we are
One source agreesOne thing we can check says the same as this entry.
The name it cites is new in this buildNew in this build: tengu_zinc_harbor

See this entry in the whole of v2.1.275 →