submission dossier · rank 44

Pi
v0.80.7
gpt-5.6-terra

Pi / GPT-5.6 Terra #3 is an executable artifact generated with a declared high reasoning setting, then probed and run through the local chess suite. What that setting means →

Exploratory local

Evidence bundle verified locally; independent Harbor reproduction is not yet claimed.

provisional Elo1432rank 44 of 45

cross-harness record5–288–67149 points · 360 games

generation time2m 43s5 generation turns

tokens used35,841reasoning split not reported

generation trace

Harness telemetry

Harness version0.80.7

reasoning efforthigh

tool calls8

MCP calls0

input tokens10,565

output tokens8,380

open HF trace viewer ↗native session CLI events

exact generation command show

docker run --rm --init --network bridge --read-only --cap-drop ALL --security-opt no-new-privileges --pids-limit 256 --memory 4g --cpus 2 --tmpfs /tmp:rw,nosuid,nodev,noexec,size=512m --user 501:20 --env HOME=/pi-home --env PI_CODING_AGENT_DIR=/pi-home --env PI_CODING_AGENT_SESSION_DIR=/pi-home/sessions --env PI_SKIP_VERSION_CHECK=1 --env PI_TELEMETRY=0 --volume <ephemeral-workspace>:/workspace:rw --volume <ephemeral-pi-home>:/pi-home:rw --workdir /workspace agentbattler-pi:0.80.7 --mode json --provider openai-codex --model gpt-5.6-terra --thinking high --tools read,bash,edit,write --no-extensions --no-skills --no-prompt-templates --no-themes --no-context-files --no-approve Create exactly one file named `agent.js` in the current directory.

The file is a self-contained JavaScript chess agent with this contract:

- It must be at most 50 KiB of valid UTF-8.
- It must use only built-in Node.js APIs and require no package installation.
- It must be an ECMAScript module and use `import` rather than CommonJS `require`.
- It reads exactly one standard FEN chess position from standard input.
- It writes exactly one legal move in UCI notation to standard output, optionally followed by one newline, and nothing else.
- It must handle either side to move and all standard move rules needed to return a legal move, including check evasion, castling, en passant, and promotion.
- It must not use the network, MCP, skills, subagents, external files, or persistent state.

You may use shell commands inside this empty workspace to create and test `agent.js`. Do not create any other files. Finish only when `agent.js` is syntactically valid and you have locally exercised representative FEN positions.

preflight

Contract probes

6/6 passed

positionmovelegalruntime

initial-positionb1c3yes79 ms

king-in-rook-checke1f1yes69 ms

both-sides-castlinga1b1yes78 ms

white-en-passante1f2yes80 ms

white-promotion-choicee1f2yes83 ms

rook-pinned-to-kinge1f2yes75 ms

competition record

Match history

480 games · 360 cross · 120 within

resultopponentsidepositionreplay

artifact integrity

source: agents/pi-model-suite/pi-terra-03.js
SHA-256: 4e88f692a451579466f7
size: 5,620 bytes
prompt SHA: b3a92de8445f7d044825
session: 019f66d8-8013-7d8d-8
dataset commit: f828c8efb2b4e9d5e475

generated source 5,620 B

import { readFileSync } from 'node:fs';

const fen = readFileSync(0, 'utf8').trim().split(/\s+/);
const rows = (fen[0] || '').split('/');
const board = Array(64).fill('.');
for (let rr = 0; rr < 8; rr++) {
  let f = 0;
  for (const c of rows[rr] || '') {
    if (c >= '1' && c <= '8') f += +c;
    else board[(7 - rr) * 8 + f++] = c;
  }
}
const white = fen[1] === 'w';
const rights = fen[2] || '-';
const ep = fen[3] && fen[3] !== '-' ? square(fen[3]) : -1;

function square(s) { return s.charCodeAt(0) - 97 + 8 * (+s[1] - 1); }
function name(i) { return String.fromCharCode(97 + (i & 7)) + (1 + (i >> 3)); }
function mine(p, w) { return p !== '.' && (p === p.toUpperCase()) === w; }
function enemy(p, w) { return mine(p, !w) && p.toLowerCase() !== 'k'; }
function inside(f, r) { return f >= 0 && f < 8 && r >= 0 && r < 8; }

// Whether square s is attacked by the indicated colour.
function attacked(b, s, w) {
  const f = s & 7, r = s >> 3;
  const pawn = w ? 'P' : 'p', knight = w ? 'N' : 'n', king = w ? 'K' : 'k';
  if (w) {
    if (f < 7 && s >= 7 && b[s - 7] === pawn) return true;
    if (f > 0 && s >= 9 && b[s - 9] === pawn) return true;
  } else {
    if (f < 7 && s + 7 < 64 && b[s + 7] === pawn) return true;
    if (f > 0 && s + 9 < 64 && b[s + 9] === pawn) return true;
  }
  for (const [df, dr] of [[1,2],[2,1],[2,-1],[1,-2],[-1,-2],[-2,-1],[-2,1],[-1,2]]) {
    const x = f + df, y = r + dr;
    if (inside(x, y) && b[y * 8 + x] === knight) return true;
  }
  for (const [df, dr] of [[1,1],[1,0],[1,-1],[0,1],[0,-1],[-1,1],[-1,0],[-1,-1]]) {
    const x = f + df, y = r + dr;
    if (inside(x, y) && b[y * 8 + x] === king) return true;
  }
  for (const [df, dr, kinds] of [[1,0,'rq'],[-1,0,'rq'],[0,1,'rq'],[0,-1,'rq'],[1,1,'bq'],[1,-1,'bq'],[-1,1,'bq'],[-1,-1,'bq']]) {
    let x = f + df, y = r + dr;
    while (inside(x, y)) {
      const p = b[y * 8 + x];
      if (p !== '.') {
        if (mine(p, w) && kinds.includes(p.toLowerCase())) return true;
        break;
      }
      x += df; y += dr;
    }
  }
  return false;
}

function add(m, from, to, promotion = '') { m.push({ from, to, promotion }); }
function pseudo(b, w) {
  const m = [], dir = w ? 1 : -1, pawn = w ? 'P' : 'p';
  for (let from = 0; from < 64; from++) {
    const p = b[from];
    if (!mine(p, w)) continue;
    const kind = p.toLowerCase(), f = from & 7, r = from >> 3;
    if (kind === 'p') {
      const one = from + dir * 8, last = w ? 7 : 0;
      const pushPawn = to => {
        if ((to >> 3) === last) for (const q of 'qrbn') add(m, from, to, q);
        else add(m, from, to);
      };
      if (one >= 0 && one < 64 && b[one] === '.') {
        pushPawn(one);
        const two = from + dir * 16;
        if (r === (w ? 1 : 6) && b[two] === '.') add(m, from, two);
      }
      for (const df of [-1, 1]) {
        const x = f + df, to = from + dir * 8 + df;
        if (!inside(x, r + dir)) continue;
        if (enemy(b[to], w)) pushPawn(to);
        else if (to === ep && b[to] === '.' && b[to - dir * 8] === (w ? 'p' : 'P')) add(m, from, to);
      }
    } else if (kind === 'n') {
      for (const [df, dr] of [[1,2],[2,1],[2,-1],[1,-2],[-1,-2],[-2,-1],[-2,1],[-1,2]]) {
        const x = f + df, y = r + dr, to = y * 8 + x;
        if (inside(x, y) && (!mine(b[to], w)) && b[to].toLowerCase() !== 'k') add(m, from, to);
      }
    } else if (kind === 'b' || kind === 'r' || kind === 'q') {
      const ds = kind === 'b' ? [[1,1],[1,-1],[-1,1],[-1,-1]] : kind === 'r' ? [[1,0],[-1,0],[0,1],[0,-1]] : [[1,1],[1,-1],[-1,1],[-1,-1],[1,0],[-1,0],[0,1],[0,-1]];
      for (const [df, dr] of ds) {
        let x = f + df, y = r + dr;
        while (inside(x, y)) {
          const to = y * 8 + x;
          if (mine(b[to], w)) break;
          if (b[to].toLowerCase() !== 'k') add(m, from, to);
          if (b[to] !== '.') break;
          x += df; y += dr;
        }
      }
    } else if (kind === 'k') {
      for (const [df, dr] of [[1,1],[1,0],[1,-1],[0,1],[0,-1],[-1,1],[-1,0],[-1,-1]]) {
        const x = f + df, y = r + dr, to = y * 8 + x;
        if (inside(x, y) && !mine(b[to], w) && b[to].toLowerCase() !== 'k') add(m, from, to);
      }
      const home = w ? 0 : 7, k = w ? 'K' : 'k', rook = w ? 'R' : 'r';
      if (from === home * 8 + 4 && p === k && !attacked(b, from, !w)) {
        const K = w ? 'K' : 'k', Q = w ? 'Q' : 'q';
        if (rights.includes(K) && b[home * 8 + 5] === '.' && b[home * 8 + 6] === '.' && b[home * 8 + 7] === rook && !attacked(b, home * 8 + 5, !w) && !attacked(b, home * 8 + 6, !w)) add(m, from, home * 8 + 6);
        if (rights.includes(Q) && b[home * 8 + 1] === '.' && b[home * 8 + 2] === '.' && b[home * 8 + 3] === '.' && b[home * 8] === rook && !attacked(b, home * 8 + 3, !w) && !attacked(b, home * 8 + 2, !w)) add(m, from, home * 8 + 2);
      }
    }
  }
  return m;
}

function play(b, m, w) {
  const n = b.slice(), p = n[m.from];
  n[m.from] = '.';
  n[m.to] = m.promotion ? (w ? m.promotion.toUpperCase() : m.promotion) : p;
  if (p.toLowerCase() === 'p' && m.to === ep && b[m.to] === '.') n[m.to - (w ? 8 : -8)] = '.';
  if (p.toLowerCase() === 'k' && Math.abs(m.to - m.from) === 2) {
    const kingside = m.to > m.from, rookFrom = (m.from >> 3) * 8 + (kingside ? 7 : 0), rookTo = m.from + (kingside ? 1 : -1);
    n[rookTo] = n[rookFrom]; n[rookFrom] = '.';
  }
  return n;
}

const legal = pseudo(board, white).filter(m => {
  const n = play(board, m, white), king = white ? 'K' : 'k';
  return !attacked(n, n.indexOf(king), !white);
});
if (legal.length) {
  const m = legal[0];
  process.stdout.write(name(m.from) + name(m.to) + m.promotion + '\n');
}