LLM Systems on Programmer.ie: Modern AI programming

From Measurements to Policy

Sun, 30 Aug 2026 18:37:00 +0100

Chapter 11 ended with a typed reliability record.

It might say:

containment          = PASS
relation_fidelity    = PASS
sensitivity          = PASS
epistemic_adequacy   = ANSWERABLE
provenance           = UNVERIFIED

That record describes the candidate.

It still does not authorize the candidate.

To make the distinction concrete, we built a deliberately flawed reference policy that checked containment, structural fidelity, and answerability but forgot to require verified provenance for a high-risk action.

Running the same immutable record through two policy versions produced:

Verification, Repair, and Rejection

Sun, 30 Aug 2026 18:38:00 +0100

Chapter 12 gave the system a control plane.

It can now say:

commitment = HOLD
next_action = VERIFY

or:

commitment = HOLD
next_action = RETRIEVE

or:

commitment = HOLD
next_action = REFINE

or:

commitment = DENY
response_mode = REJECTION

Those are policy decisions.

They are not yet recovery implementations.

The obvious implementation is dangerously tempting:

The answer failed a check.
Ask the model to fix it.

But the model that produced the first unsupported statement can produce a second unsupported statement while “correcting” it.

Building Systems That Distrust Their Models

Sun, 30 Aug 2026 21:01:00 +0100

The first chapter began with a simple observation:

A language model can produce a fluent answer
without possessing a mechanism that proves the answer is true.

Fourteen chapters later, that fact has not changed.

The model can still:

invent
misbind
misattribute
ignore decisive context
answer without enough evidence
accept bad retrieval
repair one error by creating another
repeat its own stored mistake

The final architecture does not make those possibilities disappear.