---
title: Perfect-information oracle
family: oracle-curriculum
summary: Show a planner the whole future to measure what the simulator makes possible. It is never a deployable policy.
status: completed
evidence: ledger-recorded
reads: oracle
---

A planner that is handed the entire future of a game: every disc that will
arrive and every hidden gray number — before it plays, so we can measure how
long a game *could* last if uncertainty were removed.

<EvidenceLabel status="completed" evidence="ledger-recorded" reads="oracle" />

Its own source file says it in capitals: **upper-bound diagnostic only**. It is
not a policy, it cannot be entered in any comparison with a real policy, and it
is not even a proof of the best possible cheating play, because it prunes.

## Why anyone would build this

Before spending months teaching a program to play well, it is worth knowing
whether the target is reachable at all. The qualification standard is a *mean*
above one million points, and the strongest legal search averages roughly a
third of that. Two very different worlds are consistent with that gap:

- the simulator simply does not permit long games, and a million-point average
  is arithmetically out of reach; or
- long games exist and are common enough, and the difficulty is entirely one of
  *choosing* well under uncertainty.

Removing uncertainty separates the two. If a planner that knows everything still
cannot survive, the objective is impossible. If it survives easily, then every
point of the gap is attributable to not knowing, which is the problem the rest
of the repository works on.

## How it works, step by step

1. Start a game from a seed. The harness knows the game's future disc stream and
   the reveal stream that turns gray discs into numbers.
2. At each move, plan by **beam search** over that known future: expand every
   legal column, apply the *actual* next disc and the *actual* reveals rather
   than averaging over what might happen, keep the best few thousand resulting
   positions, and repeat for a fixed number of plies. The file's defaults are
   depth 12 and beam width 512, with a 500-move cap; the runs used in later
   experiments configure it down to depth 4 and beam 128.
3. Rank the surviving plans by the score they accumulate, and play the first
   column of the best one.
4. Advance one real move and re-plan. Dying is charged an enormous penalty, so
   the planner is effectively told to survive first and score second.

Because chance has been replaced by fact, there are no
[chance nodes](/learn/concepts/chance-vs-choice) here at all: the whole thing
is a plain search over a known sequence. That is exactly what makes it illegal:
a real player choosing between seven columns does not know which of them the
next four discs will reward.

## What happened

It survives, comfortably. In a twelve-game cohort it reached the 500-move cap in
every single game and averaged over a million points, while public depth-3
search on the same games averaged about 133,000 and lived about 90 moves. In a
separate sixteen-game matched audit at a much smaller beam it still hit the
200-move cap in all sixteen and won every paired game.

So the answer to the question the oracle was built to ask is: **long games
exist**. What it did not, and cannot, show is that any of that is available to a
player who must guess. The [family page](/approaches/oracle-curriculum) collects
the several attempts to transfer it, all of which failed.

Three limitations belong in the same breath as the numbers. The cohorts were
**censored at a move cap**, so those means are lower bounds on the oracle's own
play and not comparable with uncensored games. They were scored with the
**historical 7,000-point level bonus**, which the ledger preserves as Sequence-
scored evidence and not as evidence for the Hardcore target. And the beam prunes,
so this is a *reachable* ceiling, not the true perfect-information optimum.

<TechnicalDetails>

| Cohort | Configuration | Result | Evidence |
| --- | --- | --- | --- |
| Seed `0x3d700000`, one game | receding beam over the realized tape | 2,079,579 points, stopped by the 500-move cap | ledger-recorded |
| `0x3d950000...0b`, 12 training-only games | depth 4 / beam 128, 500-move cap | capped in all 12; mean **1,058,931.5** under the historical 7,000-point level bonus; paired public depth 3 averaged 132,979 points / 90.5 moves | ledger-recorded |
| `0x3d70f000...0f`, 16 games | depth 4 / beam 128, 200-move cap, matched against public depth 3 | oracle 429,182.5 points, capped in all 16, won every pair; depth 3 90,273 / 63.625 moves; clears and reveals per move 2.354 / 1.386 against 1.792 / 0.960 | ledger-recorded, historical 7,000-point seeds |

The
[status summary](/docs/research/status) records roughly 2.4 numbered clears and
1.4 reveals per move as the region associated with stable long games, treating
those as diagnostic targets from limited runs rather than proven thresholds. The
oracle's 2.354 / 1.386 sits essentially in that region while public depth 3, at
1.792 / 0.960, does not.

Records: [experiment index](/docs/research/experiment-index) "Oracle and
curriculum research" (completed, ledger-recorded diagnostic);
[ledger](/docs/research/history), sections "Privileged-future oracle
distillation" and "Privileged topology audit". Source:
`perfect-information-oracle/main.ts`.

</TechnicalDetails>

## What this taught us, and what is still open

- The million-point objective is **not** blocked by the rules of the simulator.
  Whatever else is hard, that is settled.
- The gap between the oracle and legal search is a measure of the value of
  information, not a measure of how much better a legal policy could be. Later
  work ([`audit-05`](/docs/exploratory/audit-05-optimistic-curriculum) §5.4)
  measured how much of the oracle's edge survives when the real tape is taken
  away, and the answer was: not much, and what remains is visible as board
  quality rather than as move preference.
- The oracle remains useful as a *generator*: the positions it reaches are the
  input to the
  [state curriculum](/approaches/oracle-curriculum/state-curriculum) and the
  [topology audit](/approaches/oracle-curriculum/topology). Whether those
  positions are worth practising from is
  [still unmeasured](/docs/exploratory/audit-05-optimistic-curriculum).