Building FACET — a deterministic AI language & ecosystem for next-gen agents, world engines and autonomous systems. Engineer, founder, systems thinker, creator of SINGULAR Engine. 🚀
Great walkthrough on building agent frontends! One thing worth considering as you scale: contract specification between the frontend and agents.
The AG-UI protocol and CopilotKit are doing important work exposing agent capabilities to the frontend. But what happens when:
The agent evolves and changes what tools it can call?
The frontend needs to validate agent outputs before rendering?
You have multiple agents with different tool sets?
This is essentially the frontend/agent contract problem. Right now it's handled through implicit protocols and documentation. But as complexity grows, explicit contracts become critical.
Something like FACET could complement this approach:
Agent capability specs formally defined (not just documented)
Type-safe contracts between frontend and agent backend
Validation at the boundary — ensures agent outputs are valid before the UI renders them
Deterministic tool specifications — so the frontend always knows what the agent can do
The pattern would be:
Define agent capabilities in FACET (canonical schemas, tool specs)
CopilotKit/AG-UI consumes those specs
Frontend renders safely, knowing the contract is enforced
Excellent foundation for AI-powered UX — would love to see where you take this!
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Comprehensive tutorial. We are an AWS shop and would love to go through this starter build to see if it's a good fit for what we are trying to accomplish.
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I'm a software engineer with a background in computer science and mathematics. I specialize in developing algorithms and optimizing performance for high-performance computing systems
Great walkthrough on building agent frontends! One thing worth considering as you scale: contract specification between the frontend and agents.
The AG-UI protocol and CopilotKit are doing important work exposing agent capabilities to the frontend. But what happens when:
This is essentially the frontend/agent contract problem. Right now it's handled through implicit protocols and documentation. But as complexity grows, explicit contracts become critical.
Something like FACET could complement this approach:
The pattern would be:
Excellent foundation for AI-powered UX — would love to see where you take this!
Great write up, Rokoss.
I have learned something new today.
This is huge
Totally agree.
Learned a lot, thanks!
That's great!
I am happy to hear that, David
Comprehensive tutorial. We are an AWS shop and would love to go through this starter build to see if it's a good fit for what we are trying to accomplish.
Hey Fliin, feel free to reach out to me on Twitter @nathan_tarbert
You can talk to @nathan_tarbert.
Nice, we are building with AWS Strands. Where do I go if I get hung up?
Hi Luis, there is a CopilotKit Discord community where we'd be happy to answer your questions.
You can check out CopilotKit Discord server.
That's awesome!
I am happy to hear that.
Amazing to see a tutorial using AWS Strands agents!
Nicely done, Bonnie!
Thanks, Nathan.
Cool article saved it
I am happy to hear that, Hajeem.
Been waiting for this from copilotKit! Thanks Bonnie
I am happy to hear that, Ethan.
Great stuff and was super easy to follow!
I am happy to hear that, Eli!
Very interesting, going to share this with our team.
I am happy to hear that, Andrew.
I'm new to agents so this looks like a decent way to get started. Thanks
You are welcome, Steve.
This is great but I'm still not sure where AGUI fits in