Remove messages on close

By default a finished PR keeps its Slack message: the post is updated in place with a [Merged] or [Closed] tag and the matching reaction. The history stays in the channel.

Some teams want the opposite — a channel that only ever shows work still in flight. cleanup.delete_on_close gives you that: when the PR is merged or declined, Notifycat deletes the Slack message instead of updating it.

Off by default. Nothing changes until you turn it on.

Turning it on

Globally, for every mapped repository:

cleanup:
  message_ttl_days: 30
  delete_on_close: true

Per repository

The same key works inside a mapping tier, so one repository — or one whole org — can differ from the global setting:

cleanup:
  delete_on_close: false        # global default: keep the [Merged] message

mappings:
  acme:
    "*":
      channel: C0TEAMDEFAULT
      cleanup:
        delete_on_close: true   # every acme repo removes its messages
    archive:
      channel: C0ARCHIVE
      cleanup:
        delete_on_close: false  # …except this one, which keeps them

Inheritance is the usual most-specific-wins chain: repository tier → org "*" tier → the global cleanup: section → the built-in default (false). See Behavioral overrides.

cleanup.message_ttl_days stays global. Setting it inside a mapping tier fails startup rather than being ignored quietly.

What happens on a merge or a decline

With the flag on, for a PR that Notifycat is tracking:

1. Every Slack message for that PR is deleted — one per channel the PR fanned out to, including per-path channels. A message with a thread discussion is the exception: see Messages with a thread.
2. Any open review session is closed.
3. The PR row is dropped from the database, so the PR also leaves the stuck-PR digest immediately.

No [Merged] update and no closing reaction are sent: there is no message left to carry them. A repository's reactions settings are untouched — they still apply to reviews while the PR is open.

Merged and declined PRs behave identically. There is no way to delete on one and keep the other.

Messages with a thread

Before it deletes a message, Notifycat checks whether anyone replied in Slack its thread (reply_count on conversations.history). A message with at least one reply is kept, because deleting the parent would take the discussion with it. It gets the normal [Merged] / [Closed] tag and closing reaction instead, as if the flag were off for that one message.

The decision is per message. A PR that fanned out to two channels can lose its message in one channel and keep the threaded one in the other.

If the lookup fails — a missing scope, a Slack outage — Notifycat keeps the message and logs could not read thread replies; keeping message. An unknown thread state never risks a delete. A kept message logs kept message with thread replies.

What does not change

• The PR-open post, review reactions, and the in-review decoration all behave exactly as before.
• Converting a PR back to draft already deleted its message. That is unrelated and unaffected.
• The TTL sweep (cleanup.message_ttl_days) still runs. It only ever deleted database rows, never Slack messages, and that is still true.

Requirements and limits

• The bot needs chat:write, which it already has — Slack lets an app delete its own messages with no extra scope.
• The bot also needs channels:history and groups:history, to read the thread before a delete. Startup validation fails an entry that has the flag on while either scope is missing. See Bot scopes.
• A message somebody already deleted by hand is not an error. Slack answers message_not_found and Notifycat treats that as the outcome it wanted.
• Deleting is permanent. Slack has no undo, and Notifycat keeps no copy of the message. A message with no thread replies is gone for good.
• There is no reopen flow in Notifycat. A PR reopened after its message was deleted is not re-announced.

Which one should you pick?

	delete_on_close: false (default)	delete_on_close: true
Channel shows	every PR, finished ones tagged	only PRs still in flight
Merged PR history	stays in Slack	gone
Digest	PR drops out when closed	PR drops out when closed
Recoverable	yes	no

Pick true for a busy review channel that nobody scrolls back through. Keep the default if merged PR messages double as a record your team reads.