This is part of General Magic’s pre-smartphone technology, which has been mentioned on lobsters here.
Fun fact: when I saw the GM documentary premiere at a local indie theater, Marc Porat himself was in attendance and did a Q&A afterwards.
He’s still convinced that agent-based programming should be researched further but candidly admitted that the full implementation described here would be considered a virus(agents try to replicate themselves to the servers and run code).
The recent pushes in server-side WebAssembly remind me a little of this; I hope they take better notice of security research as well as the ability to restrict resources beyond security (probably not solve the halting problem though). Don’t want to risk an inverse of the JS model where clients are pushing servers untrusted code.