Hyperbolic Gateway
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Connect an MCP client

Hyperbolic Gateway exposes two independent MCP servers:

Server Binary Purpose
hb-browser bin/mcp-server.cjs Drives the visible Chromium browser and local memory.
hb-rest bin/wrap-server.cjs Turns saved REST requests into typed tools and renders JSON responses.

The legacy labels kuang and kuang-wrap remain accepted. New configurations should use hb-browser and hb-rest.

Minimal configuration

The Settings screen generates a correct configuration for the current installation. This is the shape it produces, with placeholders:

{
  "mcpServers": {
    "hb-browser": {
      "command": "node",
      "args": ["<repo>/bin/mcp-server.cjs"],
      "env": {
        "HB_BRIDGE_URL": "http://127.0.0.1:4111"
      }
    },
    "hb-rest": {
      "command": "node",
      "args": ["<repo>/bin/wrap-server.cjs"],
      "env": {
        "HB_WRAP_TOKEN_FILE": "<userData>/wrap/token"
      }
    }
  }
}

Use node only when Node 20+ is installed. To use the bundled Electron runtime instead, point command at the installed application and set ELECTRON_RUN_AS_NODE=1:

{
  "mcpServers": {
    "hb-browser": {
      "command": "<path-to-app>/Hyperbolic Gateway",
      "args": ["<userData>/bin/mcp-server.cjs"],
      "env": { "ELECTRON_RUN_AS_NODE": "1" }
    }
  }
}

The app must already be running. The MCP server is stateless and forwards each tool call to the local bridge.

Environment variables

hb-browser

Variable Meaning
HB_BRIDGE_URL Bridge base URL. Default http://127.0.0.1:4111.
HB_BRIDGE_TIMEOUT_MS Per-call bridge timeout. Default 300000.
HB_MCP_LOG 0 disables the file log.
HB_MCP_STDERR 0 disables the boot banner; verbose enables per-call stderr.

Legacy KUANG_BRIDGE_URL, KUANG_BRIDGE_TIMEOUT_MS, KUANG_MCP_LOG, and KUANG_MCP_STDERR are accepted as fallbacks.

hb-rest

Variable Meaning
HB_WRAP_TOKEN_FILE Path to the app-generated bridge token file. Required.
HB_WRAP_MAX_TOOLS Generated wrap_<id> cap. Default 40; 0 disables them.
HB_WRAP_TIMEOUT_MS Bridge timeout for this server.
HB_WRAP_ALLOW_PRIVATE 1 allows loopback/private API hosts.
HB_WRAP_ALLOW_HTTP 1 allows plain HTTP destinations.

Legacy KUANG_WRAP_* names are accepted as fallbacks.

Verify the connection

Call bridge_health from hb-browser. It returns the app version, page revision, capabilities, window state, and active input transport.

For hb-rest, call wrap_list. An empty list is a valid response. A 401 means the token file path is wrong, the app restarted, or the client is still holding the previous token.

Client notes

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