A Claude Code settings key, read out of the shipped bundle.
It was in the build from v2.1.138 and was gone by v2.1.284.
What happens when the background daemon is needed and none is running. With ask, if installing the daemon as a persistent service is possible here (among other checks, CLAUDE_CONFIG_DIR must be unset) and the install prompt has not been dismissed before, Claude Code returns an offer to install it (No background daemon is running. Run 'claude daemon install'...) instead of spawning one; otherwise, and with transient, it spawns a daemon for this login session. The env var CLAUDE_CODE_DAEMON_COLD_START (transient or ask) overrides the setting, and with neither set the default is ask when the tengu_quiet_harbor flag is on and transient otherwise.
Not Anthropic's. Written by Claude Opus 5.5 from reading the v2.1.283 bundle, and it can be wrong.
First seen v2.1.138 9 May 2026
Last seen v2.1.283 25 Sep 2026, gone by v2.1.284
Builds126 / 150on this box, as of v2.1.309
Written about v2.1.120 first named in a changelog, 24 Apr 2026
v2.1.138in the build not in the build never minedv2.1.309
In the changelogs
2
Releases whose published page names daemonColdStart.
No release's published evidence quotes this name. The ledger indexes the Evidence lines of every changelog on this site, so this says nobody here has ever quoted it; it says nothing about how old the name is.
Presence across releases
2
BuildsHow manyDatesReading
v2.1.138 – v2.1.283126 builds9 May 2026 → 25 Sep 2026 ◆in the build
v2.1.284 – v2.1.30924 builds28 Sep 2026 → 22 Oct 2026 ○not in the build
Build by build
150
One row per release since the first build this name was read out of. Absent means the build was read and the name was not in it, never mined means no bundle for that release was ever archived, and a declared type or a default is only ever what that release's own bundle stated.
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 settings key does. All settings keys.
