---
summary: "Loopback WebChat static host and Gateway WS usage for chat UI"
read_when:
  - Debugging or configuring WebChat access
title: "WebChat"
---

Status: the macOS/iOS SwiftUI chat UI talks directly to the Gateway WebSocket. No embedded browser, no local static server.

## What it is

- A native chat UI for the gateway.
- Uses the same sessions and routing rules as other channels.
- Deterministic routing: replies always go back to WebChat.
- History is always fetched from the gateway (no local file watching). If the gateway is unreachable, WebChat is read-only.

## Quick start

1. Start the gateway.
2. Open the WebChat UI (macOS/iOS app) or the Control UI chat tab.
3. Ensure a valid gateway auth path is configured (shared-secret by default, even on loopback).

## How it works

- The UI connects to the Gateway WebSocket and uses the `chat.history`, `chat.send`, `chat.inject`, and `chat.message.get` RPC methods.
- `chat.history` is bounded for stability: Gateway may truncate long text fields, omit heavy metadata, and replace oversized entries with `[chat.history omitted: message too large]`. API clients can send a per-request `maxChars` to override the default limit for one call.
- When a visible assistant message was truncated in `chat.history`, Control UI can open a side reader and fetch the full display-normalized entry on demand through `chat.message.get`, without increasing the default history payload. `chat.message.get` uses the same transcript branch and display rules as `chat.history`, but targets one entry by `messageId` and returns an honest unavailable reason when the full content can no longer be returned.
- `chat.history` follows the active transcript branch for append-only session files, so abandoned rewrite branches and superseded prompt copies are not rendered in WebChat.
- Compaction entries render as a "Compacted history" divider explaining that the compacted transcript is preserved as a checkpoint, with an action to open session checkpoints (branch or restore, when permissions allow).
- Control UI remembers the backing Gateway `sessionId` returned by `chat.history` and includes it on follow-up `chat.send` calls, so reconnects and page refreshes continue the same stored conversation unless the user starts or resets a session.
- `chat.send` takes an idempotency key (Control UI uses the run id); the Gateway dedupes repeated requests that reuse the same key, so retried or duplicate in-flight submits for the same session/message/attachments do not create a second run.
- Workspace startup files and pending `BOOTSTRAP.md` instructions are supplied through the agent system prompt's `# Project Context` section, not copied into the WebChat user message. If bootstrap content is truncated, the system prompt gets a short "Bootstrap Context Notice" instead; detailed counts and config knobs stay on diagnostic surfaces.
- Display normalization on `chat.history` strips: runtime-only OpenClaw context, inbound envelope wrappers, inline delivery directive tags such as `[[reply_to_current]]`, `[[reply_to:<id>]]`, and `[[audio_as_voice]]`, plain-text tool-call XML payloads (`<tool_call>`, `<function_call>`, `<tool_calls>`, `<function_calls>`, including truncated blocks), and leaked ASCII/full-width model control tokens. Assistant entries whose whole visible text is only the silent token `NO_REPLY` (case-insensitive) are omitted.
- Reasoning-flagged reply payloads (`isReasoning: true`) are excluded from WebChat assistant content, transcript replay text, and audio content blocks, so thinking-only payloads do not surface as visible assistant messages or playable audio.
- `chat.inject` appends an assistant note directly to the transcript and broadcasts it to the UI (no agent run).
- Aborted runs can keep partial assistant output visible in the UI. Gateway persists that partial text into transcript history when buffered output exists, and marks the entry with abort metadata.

### Transcript and delivery model

WebChat has two separate data paths:

- The session JSONL file is the durable model/runtime transcript. For normal agent runs, the embedded OpenClaw runtime persists model-visible `user`, `assistant`, and `toolResult` messages through its session manager. WebChat does not write arbitrary delivery, status, or helper text into that transcript.
- Gateway `ReplyPayload` events are the live delivery projection: normalized for WebChat/channel display, block streaming, directive tags, media embedding, TTS/audio flags, and UI fallback behavior. They are not themselves the canonical session log.
- Harnesses that require visible replies through `tools.message` still use WebChat as a current-run internal source reply sink. A targetless `message.send` from that active WebChat run is projected into the same chat and mirrored to the session transcript; WebChat does not become a reusable outbound channel and never inherits `lastChannel`.
- WebChat injects assistant transcript entries only when the Gateway owns a displayed message outside a normal embedded agent turn: `chat.inject`, non-agent command replies, aborted partial output, and WebChat-managed media transcript supplements.
- If live assistant text appears during a run but disappears after history reload, check in order: whether the raw JSONL contains the assistant text, whether `chat.history` display projection stripped it, then whether the Control UI optimistic-tail merge replaced local delivery state with the persisted snapshot.

Normal agent-run final answers should be durable because the embedded runtime writes the assistant `message_end`. Any fallback that mirrors a delivered final payload into the transcript must first avoid duplicating an assistant turn that the embedded runtime already wrote.

## Control UI agents tools panel

- The Control UI `/agents` Tools panel has an "Available Right Now" view backed by `tools.effective(sessionKey=...)`: a server-derived, read-only projection of the current session's tool inventory, including core, plugin, channel-owned, and already-discovered MCP server tools.
- A separate config-editing view (backed by `tools.catalog`) covers profiles, per-agent overrides, and catalog semantics.
- Runtime availability is session-scoped. Switching sessions on the same agent can change the "Available Right Now" list. If configured MCP servers have not been connected or changed since the last discovery, the panel shows a notice instead of silently starting MCP transports from the read path.
- The config editor does not imply runtime availability; effective access still follows policy precedence (`allow`/`deny`, per-agent and provider/channel overrides).

## Remote use

- Remote mode tunnels the gateway WebSocket over SSH/Tailscale.
- You do not need to run a separate WebChat server.

## Configuration reference (WebChat)

Full configuration: [Configuration](/gateway/configuration)

WebChat has no persisted config section. Gateway uses the built-in `chat.history` display limit; API clients can send per-request `maxChars` to override it for a single call. Legacy `channels.webchat` and `gateway.webchat` config is retired; run `openclaw doctor --fix` to remove it.

Related global options:

- `gateway.port`, `gateway.bind`: WebSocket host/port.
- `gateway.auth.mode`, `gateway.auth.token`, `gateway.auth.password`:
  shared-secret WebSocket auth.
- `gateway.auth.allowTailscale`: browser Control UI chat tab can use Tailscale
  Serve identity headers when enabled.
- `gateway.auth.mode: "trusted-proxy"`: reverse-proxy auth for browser clients behind an identity-aware **non-loopback** proxy source (see [Trusted Proxy Auth](/gateway/trusted-proxy-auth)).
- `gateway.remote.url`, `gateway.remote.token`, `gateway.remote.password`: remote gateway target.
- `session.*`: session storage and main key defaults.

## Related

- [Control UI](/web/control-ui)
- [Dashboard](/web/dashboard)
