Add mtime and JSON output support to the list command

[terrchen]

Hi,

Thanks for creating txcript as I've found it extremely useful and I would like to suggest a feature request to make it easier to identify what sessions has changed and to make parsing the output easier. I've currently forked txcript to add mtime (updated_at) and JSON output support for the list command.

  {
    "harness": "codex",
    "id": "...",
    "started_at": "...",
    "updated_at": "...",
    "cwd": "...",
    "path": "..."
  }

I would like this request this or something similar to be supported if possible. I can create a pull request, but this is something any capable model can do quite easily.

Thanks

[Drix10]

So the issue is valid, compared against the codebase, the Store::fingerprints()
already defines the mtime change-signal (file mtime / MAX(updated)), with amp,
antigravity, and claude_code implementing it, so updated_at is mostly surfacing
an existing signal in list, and a --format json (or --json) flag is a small,
self-contained addition with no Common type changes.

Two questions before I pick this up:

1. path: file-backed stores have a session file, but SQLite-backed ones
   (cursor, opencode) don't, should path be the store path, the reference
   debug form, or omitted/null there?
2. Flag shape: --format json (extensible later) vs --json? And should
   updated_at also become a sort key, or keep newest-first-by-started?

I would try to implement once you confirm the shape & this solution I proposed. Changes, feedbacks welcome @NishantJoshi00 @Narsagna

[terrchen]

Thanks for taking a look at this. My thoughts on this is, address the easy win which is claude, codex, and other popular agents first. For non JSONL based sessions logs, I would treat last updated as null for now. Note, this feedback is based on the fact that I haven't looked at the schema for cursor, opencode and other agents that uses a database to store sessions.

For the flag, I have no strong preference. The reason I used --format was this is how I implemented my CLI as I want to have the option to support other formats (post ai processed for example) without having to add new flags but for txcript, I think --json would work just fine.

I would make updated_at as the sort key since that is how I think most people would want to run txcript list. I think the most common use case would be to find the latest active conversations for continuation elsewhere. However, if updated_at becomes the sort key, this puts pressure on supporting opencode and cursor as it could lead to a poor experience.

So I guess the question is, is getting the last updated time from cursor and opencode a simple case of including a new field in the sql query or is there more to it?

[Drix10]

On the SQL question, I checked both.

Opencode's session table already has time_updated (it's selected in the
load path, just not in the discover query so it's one more field in the SELECT).

Cursor is file-backed with an mtime fallback helper already in place. So no nulls
needed for either; both are small.

this should work i guess:

• --json flag on list, emitting exactly your shape
  (harness/id/started_at/updated_at/cwd/path), updated_at: null only
  where a store genuinely has no signal.
• Sort by updated_at falling back to started_at, so latest-active
  surfaces first for the continue-elsewhere case.