Cross-host client
connectUI(options) is the push-first, cross-host path. It renders one Synapse
component in any host that speaks the MCP Apps standard (ChatGPT, Claude,
NimbleBrain) and standalone, behind a single façade. It is decoupled from @modelcontextprotocol/* so the
window.SynapseUI IIFE stays small.
import { connectUI } from "@nimblebrain/synapse/host";
const synapse = connectUI({ name: "my-app", version: "1.0.0" });Signature
Section titled “Signature”function connectUI(options: ConnectUIOptions): SynapseUIClient;Options
Section titled “Options”| Option | Type | Description |
|---|---|---|
name |
string |
Component name |
version |
string |
Semver version |
host |
HostKind? |
Force a host adapter. Auto-detected if omitted. |
dataElementId |
string? |
DOM element id carrying the host-injected tool-result payload |
autoResize |
boolean? |
Observe content and auto-send height. Default true |
window |
Window? |
Target window. Defaults to the current global. |
HostKind names the bridge, not the product. A framed component gets
"mcp-apps" in every host, because every host speaks that bridge; a top-level
document gets "generic":
type HostKind = "mcp-apps" | "generic";SynapseUIClient methods
Section titled “SynapseUIClient methods”| Method | Description |
|---|---|
data() |
Return the current tool-result data |
onData(cb) |
Subscribe to data changes. Returns an unsubscribe function. |
theme() |
Return the current theme |
onTheme(cb) |
Subscribe to theme changes. Returns an unsubscribe function. |
callTool(name, args) |
Call a host tool (pull) and get the result. Rejects with ToolCallError when the result reports isError: true |
sendPrompt(text) |
Send a prompt to the agent |
openLink(url) |
Open a URL via the host |
resize(height) |
Send a new height to the host |
capabilities() |
Return the detected host capabilities |
host() |
Return the detected HostKind |
destroy() |
Tear down listeners and bridges |