Web chat cannot backfill earlier Codex terminal history

[webwww123]

Summary

The web chat can only show new Codex messages after HAPI has attached to the session. It does not let me scroll back into earlier Codex terminal history.

Repro

1. Start using Codex in the terminal.
2. Open the same workflow through HAPI web.
3. Open the session in the web chat.
4. Try to scroll upward to older messages that already existed in the terminal session.

Actual behavior

• Only the new messages are available in the web UI.
• Older terminal history is missing.

Expected behavior

One of these should happen:

1. HAPI imports / backfills the earlier Codex history into the hub store so the web UI can page backward normally, or
2. The product explicitly documents that only post-attach messages are available.

Notes

This is especially noticeable when a session starts in the terminal first and the web UI is used later for continuation / monitoring.

[github-actions]

I checked the current implementation, and HAPI does not currently backfill Codex history that existed before HAPI started watching the session.

The web chat can page backward only through messages that are already stored in the hub database. For Codex local sessions, I only found code that forwards events emitted by the session scanner into the hub. I did not find a code path that imports older Codex terminal history into the hub store on first attach.

I also did not find existing docs in this repo that explicitly document this limitation.

Relevant code:

• hub/src/web/routes/messages.ts:22 - web chat reads paginated messages from the hub via GET /api/sessions/:id/messages
• hub/src/sync/messageService.ts:23 - message pages come from the hub message store, not directly from Codex session files
• cli/src/codex/codexLocalLauncher.ts:63 - Codex local mode forwards scanner events to HAPI as messages
• cli/src/codex/utils/codexSessionScanner.ts:130 - scanner startup reads existing session files during initialization
• cli/src/codex/utils/codexSessionScanner.ts:134 - initialization sets the file cursor to the current end of file
• cli/src/modules/common/session/BaseSessionScanner.ts:106 - scanner starts by initializing, then scanning from stored cursors
• cli/src/modules/common/session/BaseSessionScanner.ts:156 - scans parse from the stored cursor, so pre-existing lines are not emitted on first attach
• cli/src/api/apiSession.ts:261 - CLI backfill requires an existing lastSeenMessageSeq
• cli/src/api/apiSession.ts:272 - CLI backfill fetches only messages afterSeq, which covers reconnect gaps, not initial pre-attach import

So based on the current code, your observed behavior is real: older Codex terminal history from before HAPI attached is not backfilled into the web chat.

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HAPI Bot