[BUG] Interactive mode: manual /compact fires PreCompact but never PostCompact (print mode fires both) — v2.1.214, macOS

A data point that may narrow this down, from a different client and a newer version — SessionStart(source:"compact") does fire here.

Environment: desktop CLI ccd-cli 2.1.229 on Linux (not the macOS TUI).

On a manual /compact (compactMetadata.trigger: "manual"), my SessionStart hooks with matcher: "compact" fired and their stdout reached the model context — three registered commands, all three delivered in the same event:

21:06:42  sid=df486c1d…  emitted=compact-slice1
21:06:42  sid=df486c1d…  emitted=compact-slice2
21:06:42  sid=df486c1d…  emitted=compact-slice3

So either this was fixed between 2.1.214 and 2.1.229, or it is specific to the TUI path — the client difference seems worth checking before assuming it is still broken everywhere.

On PostCompact itself, separate from the firing problem: in this build its runner feeds userDisplayMessage, which is on-screen text rather than model context. So even when it does fire, it cannot be used to re-inject context after compaction — SessionStart with the compact matcher is the path that works. Worth documenting, because the name strongly suggests otherwise.

Could not reproduce on v2.1.233 (macOS, Apple Silicon). In interactive mode a manual /compact fired the full sequence: PreCompact → SessionStart (source: "compact") → PostCompact (trigger: "manual", with compact_summary). Print mode behaved the same.

Steps:

1. In a fresh project, add .claude/settings.json with command hooks for PreCompact, PostCompact, and SessionStart that append their stdin payload to a log file.
2. Start claude interactively and send one prompt to seed context.
3. Type /compact and press Enter (repeated once more with /compact focus on the hook setup).

Observed (hook log, both compactions):

SessionStart  source=startup
PreCompact    trigger=manual
SessionStart  source=compact
PostCompact   trigger=manual, compact_summary present
PreCompact    trigger=manual
SessionStart  source=compact
PostCompact   trigger=manual, compact_summary present

The TUI also showed PostCompact [...] completed successfully under the "Compacted" line.

Expected: exactly this, per the hooks docs (https://code.claude.com/docs/en/hooks#postcompact) — PostCompact with the manual matcher runs after /compact, in interactive and print mode alike.

Assessment: your expectation is right and the docs agree — PostCompact should fire after a manual /compact in interactive mode. On v2.1.233 it does (interactive and print mode go through the same compaction path, and both PostCompact and SessionStart with source: "compact" fire), and the comment above reports SessionStart(compact) firing on 2.1.229 too, so this appears to have been resolved somewhere between 2.1.214 and 2.1.233. Closing as fixed. If you still see PostCompact missing on v2.1.233 or later, please comment with the version, whether the hooks live in ~/.claude/settings.json or project settings, and roughly how long the compaction ran, and we'll reopen. See the changelog: https://github.com/anthropics/claude-code/blob/main/CHANGELOG.md

One clarification on the second comment: PostCompact output is intentionally display-only (its systemMessage/continue fields are ignored, per the docs). To re-inject context after compaction, use a SessionStart hook with the compact matcher.

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