Game Codex Observatory is an open record of how AI capabilities change in formal game worlds.
It is not a single leaderboard. Each result records the game, task, model snapshot, protocol version, raw trajectory, deterministic verdict, uncertainty, cost, latency, and date. Historical results are append-only: a protocol correction creates a new result rather than rewriting an old one.
Chess v0.1 covers five separable abilities:
Every task is independently repeated. A result is incomplete when the agent times out, produces an unparsable action, or cannot finish the protocol; incomplete is not silently converted into a loss or a pass.
These projects are neighbours and references, not claims of partnership or endorsement.
The primary output is a capability profile and its change over time, not one composite rank. The central question is: which failure mode stopped distinguishing models, and which one remained?
The Chess v0.1 reference baseline is a deterministic control run: 3 trials × 12 fixtures, 36/36 verdicts passed. It is not a model claim. Its purpose is to prove that the protocol, evaluator, and result schema agree before provider-backed model submissions are accepted.
The public selftest GitHub Actions workflow reruns the evaluator,
baseline, and saved-result invariants on every push and pull request with
read-only repository permissions.
External researchers can follow the submission guide. The machine-readable results registry is append-only: a new model, protocol, or reproduction gets a new entry rather than rewriting history. See the human-readable results profile for the current state without opening JSON.