Chat and Web UI¶

Reyn has two interfaces: the TUI (terminal) and the Web UI (browser). They connect to the same agent and share the same session — you can switch between them freely.

Start the TUI¶

reyn chat

The TUI gives you a > prompt. Type requests, see responses inline. It's the fastest way to start.

Start the Web UI¶

In a second terminal:

reyn web

Then open http://localhost:8080 in any browser.

The Web UI shows conversation history, running skill status, and richer output rendering (tables, code blocks, markdown). Use it when you want a more readable view or when sharing a screen.

Custom host and port¶

reyn web --port 9000            # change port
reyn web --host 0.0.0.0         # accept connections from other machines (LAN)

Security note: The default 127.0.0.1 binding accepts connections from localhost only. Use --host 0.0.0.0 only on trusted networks.

TUI and Web UI side by side¶

Both interfaces talk to the same agent. Starting a task in the TUI and then watching it in the browser works — both views update as the skill runs.

Terminal A          Terminal B          Browser
──────────────      ──────────────      ──────────────────
$ reyn chat         $ reyn web          http://localhost:8080
> write a report    (serving...)        [live progress view]

Stopping¶

TUI: Ctrl+D or /quit
Web server: Ctrl+C in the terminal where reyn web is running

The two processes are independent. Stopping one does not affect the other.

A2A endpoint (advanced)¶

The web server also exposes an A2A JSON-RPC endpoint for programmatic access and agent-to-agent communication:

POST http://localhost:8080/a2a/agents/<agent-name>

This is useful for scripting, CI pipelines, or connecting Reyn to another agent system. See concepts/a2a for the protocol details.

Troubleshooting¶

Port already in use

ERROR: [Errno 48] Address already in use

Another process is on port 8080. Use --port to pick a different one:

reyn web --port 8081

Can't connect from another device

By default the server binds to 127.0.0.1 (localhost only). Run with --host 0.0.0.0 to accept LAN connections.