AI Agent Astra Revamps Engine, Checkmates 1800-Elo Chess Bot in 31 Moves

Mike Frank's AI agent Astra got its revenge in a human-vs-AI chess match: after switching to a self-built engine under relaxed time controls, Astra checkmated the 1800-rated Wally bot in 31 moves as Black, spending only about 6 minutes more than its opponent. Frank now believes its strength clearly exceeds 1800 Elo. The case shows how a general-purpose agent, with a self-written engine and deliberate planning, can approach stronger chess AIs, and the setup is slated for open-sourcing.

Confirmed

• Astra had lost repeatedly to Wally; after several engine iterations Frank released Astra (Ultra) v0.2 with a home-grown Python game engine
• Conditions were relaxed to a 1-hour clock with flexible move timing; Astra won by checkmate playing Black (0–1)
• Mid-game Astra played a queen-rook fork, reaching a +20 evaluation
• The engine found a mate-in-two at move 29; the actual checkmate came at move 31, and Astra used only 6 minutes more than the opponent overall
• Frank published an interactive game-9 review (hosted on netlify), for the first time including the engine's per-move evaluations; the game-10 replay is also public
• Asked by thomasahle about the framework, Frank said the setup is Codex plus custom tools and skills, and he plans to open-source it on GitHub

Unconfirmed

• "Over 1800 Elo" is the author's personal estimate from play; Astra's exact rating is unmeasured, and the open-source plan has not yet materialized

Why it matters

• The case shows a general AI agent can write and iterate its own game engine rather than rely on an off-the-shelf chess engine, reaching near-1800-human strength under relaxed clocks via deliberation
• The published per-move engine-eval review gives the community verifiable material to audit Astra's real decision process; if open-sourced, the "Codex + custom tools" recipe can be reproduced and extended

2026-09-08 ~ 2026-09-08 · 6 related posts

Full story(5 episodes)→

• Episode 1: Astra Loses to 1300-Elo Chess Bot, Then Wins with Ultra Mode and Visualization Tool(2026-09-06, 7 posts)
• Episode 2: GPT-6 Astra beats chess engine with raw model output, 41-move mate(2026-09-06, 3 posts)
• Episode 3: OpenAI's Astra Loses to 1800-Elo Chess Bot After Trapped Bishop Blunder(2026-09-06, 7 posts)
• Episode 4: Astra Scores Over 1800 Elo in Chess Without Engines(2026-09-07, 5 posts)
• Episode 5: AI Agent Astra Revamps Engine, Checkmates 1800-Elo Chess Bot in 31 Moves(2026-09-08, 6 posts)

• [source] AI beats 1800-rated chess bot in 31 moves after engine upgrades, no opening book used — MikePFrank · 2026-09-08
• [source] AI agent Astra beats Wally bot at chess, finds forced mate in 2 by move 29 — MikePFrank · 2026-09-08
• [source] Astra's home-grown chess engine beats Wally, finds forced mate in 2 by move 29 — MikePFrank · 2026-09-08
• Chess AI Astra beats Wally with 6 extra minutes; author estimates it's now well above 1800 ELO — MikePFrank · 2026-09-08
• Self-built AI engine Astra (Ultra) beats Wally, author claims 1800+ ELO — MikePFrank · 2026-09-08
• GPT-6 Astra plays chess well above 1800 ELO, says researcher after tests — thomasahle · 2026-09-08