How it works

browser page  ──►  server.py :8474  ──►  hark --remote-control :8473
     ▲                  │                          │
     └── transcript ────┴──── reads ◄── writes ────┘
                     ~/Recordings/calls/…

server.py is a single standard-library Python file, and the page is viewer.html. The server serves the page and the call folders, and forwards the control requests to hark's remote-control agent. The page cannot call the agent directly because the agent sends no CORS headers. The server starts the agent when it is not running.

API

Request	Does
GET /api/status	Agent state, the active session, the call it belongs to, its number of parts, the postprocess state of that call, the workspace folders, and patience, the longest a start can take. The session goes through as hark sent it, so it carries partial while a streaming hark has a line open, callAudio on a hark that checks its capture and capturing on one that disowns it, and none of those keys otherwise
POST /api/new with {"workspace", "title"}	Creates the call folder and starts recording
POST /api/restart	Stops the recording and starts the next part in the same call folder. Answers {"call", "part"}, or 409 when there is no call it may restart: none open, one that already has its accurate transcript, or one last written over an hour ago unless the body is {"force": true} (see Troubleshooting)
POST /api/stop, /pause, /resume, /mute, /unmute	Forwarded to hark
GET /<call>/transcript.json	The live transcript. For a restarted call, every part joined on the call's clock

Every POST needs the header X-Hark-Viewer: 1.

What it asks hark to record

The START dictionary at the top of server.py holds what hark records with: system audio with the microphone mixed in, speaker labels, the Core Audio backend, tracks: stereo so the microphone and the call stay on their own channels, liveStreaming for the line still being spoken, and ifExists: error so hark never writes over a recording. A hark that does not know a key ignores it.

The environment settings and their defaults are on Configuration; the START settings are the ones above.