submission dossier · rank 42

Pi
v0.80.7
gpt-5.6-terra

Pi / GPT-5.6 Terra #1 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 Elo1434rank 42 of 45

cross-harness record5–297–58153.5 points · 360 games

generation time2m 3s8 generation turns

tokens used46,687reasoning split not reported

generation trace

Harness telemetry

Harness version0.80.7

reasoning efforthigh

tool calls7

MCP calls0

input tokens10,943

output tokens6,048

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-positiona2a3yes84 ms

king-in-rook-checke1e2yes78 ms

both-sides-castlinge1g1yes73 ms

white-en-passante5e6yes77 ms

white-promotion-choicea7a8qyes78 ms

rook-pinned-to-kinge2e3yes99 ms

competition record

Match history

480 games · 360 cross · 120 within

resultopponentsidepositionreplay

artifact integrity

source: agents/pi-model-suite/pi-terra-01.js
SHA-256: cd5add65c50601f46da5
size: 5,264 bytes
prompt SHA: b3a92de8445f7d044825
session: 019f66c4-5118-7d5c-a
dataset commit: f828c8efb2b4e9d5e475

generated source 5,264 B

import { readFileSync } from 'node:fs';

const fen = readFileSync(0, 'utf8').trim().split(/\s+/);
const rows = fen[0].split('/');
let b = [];
for (const row of rows) for (const x of row) {
  if (x >= '1' && x <= '8') b.push(...Array(+x).fill('.'));
  else b.push(x);
}
const turn = fen[1], rights = fen[2] || '-', ep = fen[3] || '-';
const epSq = ep === '-' ? -1 : (8 - +ep[1]) * 8 + ep.charCodeAt(0) - 97;
const white = p => p >= 'A' && p <= 'Z';
const mine = (p, s) => p !== '.' && white(p) === (s === 'w');
const opp = s => s === 'w' ? 'b' : 'w';
const rc = i => [i >> 3, i & 7];
const sq = i => String.fromCharCode(97 + (i & 7)) + (8 - (i >> 3));

function attacked(a, target, side) {
  const [tr, tc] = rc(target);
  for (let i = 0; i < 64; i++) {
    const p = a[i];
    if (!mine(p, side)) continue;
    const q = p.toLowerCase(), [r, c] = rc(i);
    if (q === 'p') {
      const d = side === 'w' ? -1 : 1;
      if (r + d === tr && Math.abs(c - tc) === 1) return true;
    } else if (q === 'n') {
      if ((Math.abs(r - tr) === 1 && Math.abs(c - tc) === 2) ||
          (Math.abs(r - tr) === 2 && Math.abs(c - tc) === 1)) return true;
    } else if (q === 'k') {
      if (Math.max(Math.abs(r - tr), Math.abs(c - tc)) === 1) return true;
    } else {
      const diagonal = Math.abs(r - tr) === Math.abs(c - tc);
      const straight = r === tr || c === tc;
      if (!((q === 'b' && diagonal) || (q === 'r' && straight) ||
            (q === 'q' && (diagonal || straight)))) continue;
      const dr = Math.sign(tr - r), dc = Math.sign(tc - c);
      let rr = r + dr, cc = c + dc, clear = true;
      while (rr !== tr || cc !== tc) {
        if (a[rr * 8 + cc] !== '.') { clear = false; break; }
        rr += dr; cc += dc;
      }
      if (clear) return true;
    }
  }
  return false;
}

function pseudo(a, side) {
  const out = [], add = (f, t, extra = {}) => out.push({ f, t, ...extra });
  for (let f = 0; f < 64; f++) {
    const p = a[f];
    if (!mine(p, side)) continue;
    const q = p.toLowerCase(), [r, c] = rc(f);
    if (q === 'p') {
      const d = side === 'w' ? -1 : 1, start = side === 'w' ? 6 : 1, last = side === 'w' ? 0 : 7;
      const one = (r + d) * 8 + c;
      const put = t => add(f, t, r + d === last ? { promo: side === 'w' ? 'Q' : 'q' } : {});
      if (r + d >= 0 && r + d < 8 && a[one] === '.') {
        put(one);
        const two = (r + 2 * d) * 8 + c;
        if (r === start && a[two] === '.') add(f, two);
      }
      for (const dc of [-1, 1]) {
        const rr = r + d, cc = c + dc;
        if (rr < 0 || rr > 7 || cc < 0 || cc > 7) continue;
        const t = rr * 8 + cc;
        if (mine(a[t], opp(side))) put(t);
        else if (t === epSq && a[t + (side === 'w' ? 8 : -8)] === (side === 'w' ? 'p' : 'P')) add(f, t, { ep: true });
      }
    } else if (q === 'n' || q === 'k') {
      const ds = q === 'n' ? [[-2,-1],[-2,1],[-1,-2],[-1,2],[1,-2],[1,2],[2,-1],[2,1]] :
        [[-1,-1],[-1,0],[-1,1],[0,-1],[0,1],[1,-1],[1,0],[1,1]];
      for (const [dr, dc] of ds) {
        const rr = r + dr, cc = c + dc;
        if (rr >= 0 && rr < 8 && cc >= 0 && cc < 8 && !mine(a[rr * 8 + cc], side)) add(f, rr * 8 + cc);
      }
      if (q === 'k') {
        if (side === 'w' && f === 60) {
          if (rights.includes('K') && a[61] === '.' && a[62] === '.' && a[63] === 'R') add(f, 62, { castle: true });
          if (rights.includes('Q') && a[59] === '.' && a[58] === '.' && a[57] === '.' && a[56] === 'R') add(f, 58, { castle: true });
        }
        if (side === 'b' && f === 4) {
          if (rights.includes('k') && a[5] === '.' && a[6] === '.' && a[7] === 'r') add(f, 6, { castle: true });
          if (rights.includes('q') && a[3] === '.' && a[2] === '.' && a[1] === '.' && a[0] === 'r') add(f, 2, { castle: true });
        }
      }
    } else {
      const ds = q === 'b' ? [[-1,-1],[-1,1],[1,-1],[1,1]] : q === 'r' ? [[-1,0],[1,0],[0,-1],[0,1]] :
        [[-1,-1],[-1,0],[-1,1],[0,-1],[0,1],[1,-1],[1,0],[1,1]];
      for (const [dr, dc] of ds) for (let rr = r + dr, cc = c + dc; rr >= 0 && rr < 8 && cc >= 0 && cc < 8; rr += dr, cc += dc) {
        const t = rr * 8 + cc;
        if (mine(a[t], side)) break;
        add(f, t);
        if (a[t] !== '.') break;
      }
    }
  }
  return out;
}

function apply(a, m, side) {
  const n = a.slice();
  n[m.t] = m.promo || n[m.f]; n[m.f] = '.';
  if (m.ep) n[m.t + (side === 'w' ? 8 : -8)] = '.';
  if (m.castle) {
    if (m.t === 62) { n[61] = n[63]; n[63] = '.'; }
    else if (m.t === 58) { n[59] = n[56]; n[56] = '.'; }
    else if (m.t === 6) { n[5] = n[7]; n[7] = '.'; }
    else { n[3] = n[0]; n[0] = '.'; }
  }
  return n;
}

function legal(m) {
  if (m.castle) {
    const pass = m.f + (m.t > m.f ? 1 : -1);
    if (attacked(b, m.f, opp(turn))) return false;
    const mid = b.slice(); mid[pass] = mid[m.f]; mid[m.f] = '.';
    if (attacked(mid, pass, opp(turn))) return false;
  }
  const n = apply(b, m, turn), king = n.indexOf(turn === 'w' ? 'K' : 'k');
  return king >= 0 && !attacked(n, king, opp(turn));
}

const candidates = pseudo(b, turn);
const move = candidates.find(m => m.castle && legal(m)) || candidates.find(legal);
if (move) process.stdout.write(sq(move.f) + sq(move.t) + (move.promo ? move.promo.toLowerCase() : ''));