carry-thread

name	carry-thread
description	Move THIS conversation onto a fresh Slack thread, keeping the same agent session and everything it remembers. ONLY TRIGGER when the user EXPLICITLY asks to continue the current conversation somewhere else — e.g. "continue this in a new thread", "move this to a fresh thread", "same conversation, new thread", "this thread is too long, carry on in a new one". NEVER trigger on your own initiative. Never carry because a thread looks long, cluttered, or busy — if the user did not ask, keep replying where you are. This is NOT for starting separate work: if the user wants a NEW task in its own thread with a fresh start, that is the spawn-thread skill instead. Carrying MUTES the thread you are in, so doing it unasked strands whoever is talking to you.
allowed-tools	Bash
argument-hint	--opener "<the message that opens the new thread>" # --opener consumes remaining tokens

carry-thread

Moves the current agent session onto a new top-level Slack thread. The conversation keeps its memory — it is the same session at a new address.

bun features/slack/skills/carry-thread/scripts/index.ts \
  --opener ":thread: Continuing here — the other thread got long."

The thread being carried is the one this turn is running in, read from $SLACK_CHANNEL_ID / $SLACK_THREAD_TS. There is no --channel flag: a conversation cannot be carried into a channel its participants may not be in.

What happens

1. An anchor reply is posted into the current thread, then rewritten to link forward to the new one.
2. A top-level message is posted with the opener and a View originating thread button pointing back.
3. POST /slack/thread/carry (loopback-guarded) moves the session binding onto the new thread and mutes the old one.
4. A closing line is posted in the old thread saying where the conversation went.

Prints {"ok":true,"channel":"C...","thread_ts":"...","sessionId":"..."} and exits 0. Exits 1 with a reason on failure.

When it refuses

• The current thread has never run a turn (HTTP 422). There is no session to carry — the user wants spawn-thread new.
• The current thread is mid-turn (HTTP 409). Rebinding underneath a running turn would hand the new thread a session the old turn is still writing to. Wait for the run to finish and carry again.
• No thread in scope. SLACK_CHANNEL_ID / SLACK_THREAD_TS unset.

On a failure after the new thread was already posted, the reason is posted into the ORIGINAL thread — that is where the user is looking — and the session stays where it was.

Why not spawn-thread

spawn-thread new opens a thread and lets the daemon mint a fresh session: the new thread knows only what you put in its prompt. Use it for separate work. carry-thread keeps the same session. Use it when the user means "this conversation, elsewhere".