The Actor–Critic

The loop that grades itself

The last archetype attacks a different weakness. Everything we've built produces artifacts — reports, plans, code, designs — and a first draft of anything is rarely right. The fix is a loop older than software: one party produces, an independent party criticizes, the producer repairs — until the work passes. The name comes from a long tradition (reinforcement learning calls its version actor–critic), and the theater thread makes it feel inevitable: every play needs its critic.

One classification before we run it, because it marks a border in the archetype family. The Explorer and the Scientist live in a single conversation — one wall, one trajectory. The Actor–Critic is our first multi-conversation archetype: two minds that never share a wall, coupled through a third thing — the artifact. The actor builds and modifies it; the critic observes and critiques it; it is the only object they have in common. And the reason for two minds is not redundancy — it is that building and checking are different attentions:

THE ACTOR builds. Its attention lives inside the work —
making choices, holding structure, moving forward. Building
attention is forward-looking, and it reliably misses things:
a builder reads what they MEANT, not what is on the page.

THE CRITIC observes. Its attention has exactly one job:
completeness and correctness against the bar. It builds
nothing, wants nothing, moves nothing forward.

Between them sits the ARTIFACT — written by one attention,
read by the other. Neither attention can do both jobs at
once; that is why there are two seats.

Now watch it run.

The grant package

The task: assemble a grant proposal package — narrative, budget, references — under a funder's hard rules and soft expectations.

Why the critic must be independent

Here is the deepest design rule of the archetype, and it comes straight from the self-conditioning thread. Suppose the actor checks its own draft, in its own conversation. That wall contains every reason the draft looks the way it does — each decision, already justified, each phrasing already approved once by the very trajectory that produced it. Asking that conversation "is this good?" invites the answer the trajectory has been building toward all along: yes.

The actor cannot grade its own homework on its own wall.

A critic must be a FRESH conversation: the draft, the bar,
and nothing else. It has never met the reasons. It reads
what is actually on the page — which is exactly what the
funder will do.

(Fresh eyes are a firebreak against self-agreement —
the same reason the compaction scribe and the ask-the-
document tool were disposable conversations.)

There's a second, quieter benefit: the critic's wall is small — the draft and the bar, no history — so its judgment runs at full attention. Producer walls bloat; verifier walls are born clean, every round.

The bar and the budget

Two contracts keep the loop honest, both written before it starts:

That last observation ties the room together: the archetypes compose. An actor–critic loop can sit as one stage inside a Planner–Executor's plan; the Designer's simulate step is a code critic; the Scientist's discriminating test is criticism aimed at hypotheses. The four archetypes aren't rival architectures — they are shapes that nest.

Where the actor–critic earns its cost

The loop doubles LLM spend per round — producer and critic both think. It pays for itself where: