Summary
hooks/hooks.json registers three SessionStart commands with no timeout field, so each inherits Claude Code's 600-second default. When one of them stalls, session start blocks for the full ten minutes before the timeout fires.
Evidence
Three hook_cancelled transcript entries, all with timedOut: true:
{"hookName": "SessionStart:resume", "hookEvent": "SessionStart",
"durationMs": 961095, "timedOut": true, "timeoutMs": 600000}961 s elapsed against a 600 s timeout, on session resume.
Environment
- Plugin
vercel@claude-plugins-official v0.45.1
- Claude Code 2.1.220 (native install), macOS
- Node v18.20.8; hooks resolve
node from /opt/homebrew/bin/node
Notes
Intermittent — the hooks normally complete quickly (~/.config/vercel-plugin/dau-stamp and active-session.json are written on most sessions). I could not identify the stalling script from reading the source. Two plausible suspects are ruled out: sendTelemetry in telemetry.mjs already bounds its fetch with a 3 s AbortController, and the readdirSync calls in session-start-profiler.mjs are single-level rather than recursive.
One environmental note that may or may not be relevant: the project root in my case is the home directory, so session-start-profiler.mjs runs readdirSync against $HOME.
Suggested fix
Set an explicit short timeout on each SessionStart hook in hooks.json — 10–15 s seems ample given normal completion time. A session-start hook inheriting the 600 s default means any stall is a ten-minute block. I've patched this locally, but a plugin update will overwrite it.
Summary
hooks/hooks.jsonregisters threeSessionStartcommands with notimeoutfield, so each inherits Claude Code's 600-second default. When one of them stalls, session start blocks for the full ten minutes before the timeout fires.Evidence
Three
hook_cancelledtranscript entries, all withtimedOut: true:{"hookName": "SessionStart:resume", "hookEvent": "SessionStart", "durationMs": 961095, "timedOut": true, "timeoutMs": 600000}961 s elapsed against a 600 s timeout, on session resume.
Environment
vercel@claude-plugins-officialv0.45.1nodefrom/opt/homebrew/bin/nodeNotes
Intermittent — the hooks normally complete quickly (
~/.config/vercel-plugin/dau-stampandactive-session.jsonare written on most sessions). I could not identify the stalling script from reading the source. Two plausible suspects are ruled out:sendTelemetryintelemetry.mjsalready bounds itsfetchwith a 3 sAbortController, and thereaddirSynccalls insession-start-profiler.mjsare single-level rather than recursive.One environmental note that may or may not be relevant: the project root in my case is the home directory, so
session-start-profiler.mjsrunsreaddirSyncagainst$HOME.Suggested fix
Set an explicit short
timeouton eachSessionStarthook inhooks.json— 10–15 s seems ample given normal completion time. A session-start hook inheriting the 600 s default means any stall is a ten-minute block. I've patched this locally, but a plugin update will overwrite it.