Show HN: Specification First Agentic Development Plugin and Prove
Implemented agent smith since start 2026 with over 1000 specifications which lead to about 500k lines of code. The procedure with that spec-first works well. How do you do it?
Implemented agent smith since start 2026 with over 1000 specifications which lead to about 500k lines of code. The procedure with that spec-first works well. How do you do it?
Discussion Highlights (8 comments)
cassianoleal
If your specs are not executable or are editable by the agent, they are as non-deterministic as any code that comes out of them.
woeirua
I have not seen spec first development work well in real world environments at all. The problem is that you typically don't know what you don't know upfront for most product based decisions. Going back and forth in the spec to fix problems is a huge mistake, it just leads to contradictory sets of requirements for the agent. What does work well is using AI to generate a quick and dirty prototype ala vibecoding, and then using that as a basis to regenerate the final code. Some might say it's still spec driven development, but the spec is a working prototype.
memjay
Always reminds me of this meme. Some day we won't even need coders any more. We'll be able to just write the specification and the program will write itself. Oh wow, you're right! We'll be able to write a comprehensive and precise spec and bam, we won't need programmers any more! Exactly! And do you know the industry term for a project specification that is comprehensive and precise enough to generate a program? Code It's called code.
systima
How does this differ to Spec Kit / BMAD / etc?
_ink_
What is the difference between having the agent create a spec and having the agent create a plan?
StephenTynan789
its crazy how capable the agents are becoming so quickly
whattheheckheck
A spec should use orthodox tools and formats for higher level system descriptions. Like a BPMN file, a TLA+ state machine model, a P/ModP or Event B system. Llms compile that into a binary and you deploy it and present it and users use it and they're happy or not. There's just so many different projections of how to describe a system. What's the moat bang for the buck.
evulhotdog
I’ve recently adopted openspec for one of our repos and it’s worked great. Openspec is already decently well established and has a lot of support for all the different harnesses that exist. I’m really starting to enjoy it for helping flush out the ideas in my head into something real and tangible.