I ran each AI coding-agent sandbox's own tests against the others

An open lab that turns sandbox claims (no key reads, no network, no git hooks) into runnable contracts and publishes results across sandboxes on the same tests. Corpus v1.1 (2026-10-26) holds 196 contracts harvested from the public test suites of sandbox-runtime, nono, Codex, Deno, bubblewrap and OpenHands, each re-expressed in a neutral format and credited. First results measure sandbox-runtime 0.0.79, nono 0.80.0, Codex CLI 0.162.1 and landrun on Linux kernel 6.8, with later runs adding TartarOS and masked-credential contracts.