Chrome DevTools' MCP Server Can Now Inspect a Page Without Running Its Scripts

Buried in Chrome's September DevTools recap for versions 153 and 154 is a flag worth knowing about. The DevTools MCP server now has a --no-javascript-evaluation option, which lets an AI agent inspect a page without running scripts against it.

That matters more than it sounds. Pointing an agent at a live site is useful for checking console errors, network calls and layout, but an agent that can evaluate arbitrary JavaScript can also change state on a page it should only be reading. A client's production checkout is not the place for that.

Our take: use the read-only mode by default for anything that is not a local dev build. If an audit needs script evaluation, turn it on deliberately, on a staging copy, for that task only.

The same update adds on-demand source maps to cut memory use on large sites, plus a query_heapsnapshot tool for digging into memory problems. Those are useful, but the flag is the one that changes how safely you can hand an agent the keys.

Chrome now ships on a two-week cadence, so these recaps will keep arriving. It is worth skimming each one for the small controls that change what you are comfortable delegating.