Codex GPT-6.1 Sol: Why Does It Assume Instead of Verify?

I genuinely hate working with Codex's GPT-6.1 Sol.

My biggest frustration? It would rather assume than verify.

Instead of establishing a factual, grounded understanding of the codebase, requirements, or documentation, it jumps straight to conclusions. Those assumptions snowball into inaccurate implementations, unnecessary changes, and wasted time.

And don't get me started on the overengineering.

It overthinks everything, complicates simple problems, and somehow manages to be incredibly lazy when it comes to verifying the basics.

The irony? It spends so much effort thinking about solutions without first establishing whether its assumptions are even correct.

I've tried giving it guardrails. Ponytails. Even Matt Pocock's grill-with-docs skill, which is intended to encourage thorough investigation, subagents, and fact-grounded decisions.

Yet somehow, none of it seems to tame this insufferable habit.

I have to explicitly tell it to stop assuming and start verifying. Every. Single. Time.

That's what pisses me off the most. A supposedly capable coding agent shouldn't need constant babysitting just to establish facts before making decisions.

I don't mind an agent spending more time reasoning if it produces better results. But overthinking and overengineering are not substitutes for understanding the actual problem.

I shouldn't have to repeatedly instruct a coding agent to inspect the existing implementation, consult documentation, or validate its conclusions before making changes. Those should be fundamental practices.

It's not that I want a model that thinks less. I want a model that verifies more and assumes less.

For starting a new project, where understanding the requirements and establishing the right foundations matter most, GPT-6.1 Sol has been an incredibly frustrating experience.

And this is coming from someone who genuinely enjoys working with AI coding agents. I want these tools to succeed, but having to constantly supervise their reasoning defeats much of the purpose of using them in the first place.

I'm curious about the experience of other developers and vibe coders in KD.

Have you guys experienced the same issues with GPT-6.1 Sol or other Codex models? Or have you found a workflow that actually keeps them grounded without constant babysitting?