ohos-chrome-devtools-mcp

Thin wrapper that lets chrome-devtools-mcp drive the ArkWeb browser on an OpenHarmony / HarmonyOS device. The OHOS counterpart of the upstream Chrome DevTools MCP server.

The MCP surface — tools, behaviour, output formats — is the upstream chrome-devtools-mcp verbatim. This wrapper exists only to do the OHOS-specific hdc dance:

1. Connect to the device (auto-discovery via hdc tconn, or a manual paste fallback).
2. Locate the ArkWeb browser process and its @webview_devtools_remote_<pid> abstract socket.
3. Forward that socket to a local TCP port with hdc fport.
4. Spawn chrome-devtools-mcp with --browserUrl=http://127.0.0.1:<port> and pipe its stdio straight through.

When the wrapper exits, the hdc fport rule is cleaned up.

Install

npm i -g ohos-playwright@^0.6.0 ohos-chrome-devtools-mcp@^0.2.0 chrome-devtools-mcp

ohos-playwright and chrome-devtools-mcp are peer dependencies — npm 7+ installs them alongside automatically when you install this package globally.

Compatibility

ohos-chrome-devtools-mcp	ohos-playwright
0.2.x	≥0.6.0
0.1.x	≥0.2.9

ohos-playwright 0.6.0+: MainAbility (multi-tab browser) is the default. CustomTabAbility (single-page) is available via OHOS_PW_CUSTOM_TAB=1.

MCP client configuration

{
  "mcpServers": {
    "ohos-chrome-devtools": {
      "command": "ohos-chrome-devtools-mcp",
      "args": []
    }
  }
}

Any additional flags accepted by the upstream chrome-devtools-mcp can be appended to args — they are forwarded as-is, with a short blocklist for flags that would conflict with the connect-only flow (see Stripped flags).

How it differs from chrome-devtools-mcp

	upstream chrome-devtools-mcp	this wrapper
Target browser	Chrome (launched locally)	ArkWeb on an OHOS device, over hdc
Setup	Puppeteer launches Chrome	ohos-playwright/setup (hdc connect + fport)
Connection	--browserUrl / --wsEndpoint / --channel	always connects via --browserUrl (injected)
Tool surface	full upstream API	identical — wrapper does not modify it

Stripped flags

These flags would make chrome-devtools-mcp ignore the OHOS device and either launch a local Chromium or connect somewhere unintended. The wrapper silently drops them with a stderr note:

• --browserUrl (we set this from the device endpoint)
• --wsEndpoint
• --channel
• --userDataDir
• --executablePath
• --isolated

Environment

Configuration is inherited from ohos-playwright. The most useful variables:

Variable	Default
OHOS_PW_HDC	/data/service/hnp/bin/hdc
OHOS_PW_BUNDLE	com.huawei.hmos.browser
OHOS_PW_LAUNCH_URL	about:blank
OHOS_PW_AUTO_CONNECT	auto (set 0 to skip auto-connect)
OHOS_PW_INFO_PATH	<tmpdir>/ohos-playwright-cdp.json

Wrapper-specific overrides (rarely needed):

Variable	Purpose
OHOS_CDT_SETUP	absolute path to a custom setup module
OHOS_CDT_TEARDOWN	absolute path to a custom teardown module
OHOS_CDT_BIN	absolute path to a chrome-devtools-mcp bin to spawn

Troubleshooting

• Cannot resolve "ohos-playwright/setup" — install ohos-playwright (npm i -g ohos-playwright) or set OHOS_CDT_SETUP.
• Cannot resolve "chrome-devtools-mcp/package.json" — install upstream (npm i -g chrome-devtools-mcp) or set OHOS_CDT_BIN.
• ohos-playwright setup finished but ... was not written — usually a stale hdc tconn / sandbox-blocked device. Run hdc list targets to check.
• The upstream chrome-devtools-mcp server writes its own diagnostics to stderr; check stderr first when a tool fails.

License

MIT