I'm building NextStep — an AI thing that scores your resume against a job and rewrites it to fit. Two features, both completely dependent on the model not lying. And GPT-4o loves to lie.
Two bugs made me stop trusting it:
Score the same resume twice → 87, then 79. Cool, so the number means nothing.
Ask it to "optimize for this DevOps role" → it adds "Managed production Kubernetes clusters" to a guy who's never opened a terminal. That's not a typo, that's getting someone caught lying in an interview.
So I stopped treating the model like it knows things. I treat its output like a request body from some random client: assume it's garbage until I've checked it.
