Web control center

An optional page served on 127.0.0.1 only. It traces every turn end to end and controls the koda that is running — not a copy of its config on disk, the live process.

Serving the web control center100×30 · 0:19

web_ui = true makes koda serve its trace waterfall and prompt inspector on 127.0.0.1 — loopback only, and only alongside the TUI: a headless `-p` run starts no server, as this shows.

Turning it on

Open /settings and toggle web ui on, or set it in the config:

web_ui = true
web_ui_port = 7717     # optional; the default
ui_detail = "medium"   # simple | medium | high

The settings toggle is remembered, and koda starts the server on the next launch. On launch it prints the address:

koda: web UI at http://127.0.0.1:7717

Turn tracing is on whenever the web UI is. KODA_TRACE=1 forces it on otherwise. The last 50 turns are kept in memory with truncated payloads, so a long session stays bounded.

What is on the page

Turn rail — every turn, newest first, with status, duration, step and token counts. The running turn is followed live.

Trace waterfall — that turn’s steps in order, with duration bars: model calls, tool calls and compactions, with retries, failures and denied approvals marked inline.

Inspector — the payloads behind a step: the exact request body sent, the raw SSE stream received, the model’s reasoning, and a tool’s arguments, result and diff.

Prompt Δ is the part worth knowing about. It diffs the prompt against the previous model call, so what compaction dropped — or what a learned rule added — is visible rather than silent. When a turn goes wrong three steps in, this is usually where the reason is.

Control rail — model, endpoint, mode, autonomy tier, reasoning effort, max steps, feature toggles, project memory, learned-rule candidates, and saved sessions to resume or fork. Edits apply to the running koda, not just to disk.

Logs drawer (L) and a Manage panel for the code graph, skills and role agents, the system prompt, and raw request/response captures.

⌘K command palette — jump to a turn, switch model or mode, toggle a feature, export a trace, or @symbol + shift+enter to query the code graph.

Raw captures are separate

The trace does not need /debug. Raw request and response files are a different thing: enable /debug (or debug = true, or KODA_DEBUG=1) to fill the Manage panel’s Raw Captures and write them to ~/.local/state/koda/debug/.

What it costs

Nothing you have not already installed. The server is built on the async runtime koda already uses, adds no dependencies, and binds to localhost only — nothing is exposed off your machine.

The Agents & Skills page has a provider dropdown populated from your saved providers, and a model box that suggests what that provider actually serves while still accepting free text. The web UI never receives your API keys: the provider list reports only whether a key is set.