Runtime platforms and limitations
Agentic Development Toolkit (ADT) Web Viewer apps are built during development, then deployed into FileMaker. Once deployed, the runtime environment is FileMaker itself — see How Embedded Deployment Works for what "deployed" means and System Requirements for the full development-versus-runtime breakdown.
FileMaker Pro (development)
FileMaker Pro is required for the agentic development workflow, but not for every command. Type generation, deploy, and the MCP data tools need your file open in FileMaker Pro with Agent Access turned on — see fmBridge() for how that connection works. Schema, script, and layout work through the filemaker CLI needs only a file address recorded in adt.json, with FileMaker Pro closed if you like. See Projects, Connected Files, and Apps for the two lanes.
Warning macOS only, for now ADT requires a Mac. Windows is not a supported development target today.
FileMaker Pro (runtime)
Once deployed, a Web Viewer app runs anywhere FileMaker itself supports Web Viewers, including FileMaker Pro on macOS and Windows. Because ADT is pre-release software and production use is not permitted, treat any platform beyond FileMaker Pro on macOS as unverified until you've tried it against your own file.
WebDirect
Deployed Web Viewer apps can also run in WebDirect, but browser refresh and session behavior need special care — a browser refresh restarts the WebDirect session, not just the Web Viewer. Avoid designs that assume a user can freely refresh the page without affecting their FileMaker session.
If your app needs to know whether it's running under WebDirect, let FileMaker tell it rather than sniffing the browser. The app template's initial-props pattern can pass a script-calculated isWebDirect flag into the app before the first route renders — see the getInitialPropsScriptName option in the template's router setup.
End users
End users do not need ADT installed. They need only the FileMaker runtime where the Web Viewer app was deployed — FileMaker Pro or WebDirect, per the table below.
Development versus runtime
| Requirement | Development | Runtime |
|---|---|---|
| Mac | Yes | No |
| ADT installer | Yes | No |
| FileMaker Pro | Yes 1 | Optional |
| Node.js, pnpm | Only for apps 2 | No |
| Coding agent with the ADT plugin | Yes | No |
| Deployed Web Viewer bundle | Created here | Runs here |
1 Installed and runnable always; running with the file open and Agent Access turned on for type generation, deploy, and the MCP data tools.
2 Node.js 24+ and pnpm 11+ are needed only once you build a Web Viewer app with adt app add. The adt CLI is a compiled binary.
See System Requirements for what a development machine needs.