AutomationBench

Private held-out board; simulated business-workflow app APIs; all assertions must pass; max effort stated for Fable5.1/Opus5.

Fable is the safeguarded deployed configuration; selected tasks may use disclosed Opus fallback, except evaluations explicitly counting safety blocks as failures.

Claude Fable 5.1 and Claude Mythos 5.1 System Card · Table8.1.A;8.15.6 · reviewed 2026-09-24

Private held-out board; simulated business-workflow app APIs; all assertions must pass; max effort stated for Fable5.1/Opus5.

Claude Fable 5.1 and Claude Mythos 5.1 System Card · Table8.1.A;8.15.6 · reviewed 2026-09-24

Private held-out board; simulated business-workflow app APIs; all assertions must pass; max effort stated for Fable5.1/Opus5.

Claude Fable 5.1 and Claude Mythos 5.1 System Card · Table8.1.A;8.15.6 · reviewed 2026-09-24

Private held-out board; simulated business-workflow app APIs; all assertions must pass; max effort stated for Fable5.1/Opus5.

Fable is the safeguarded deployed configuration; selected tasks may use disclosed Opus fallback, except evaluations explicitly counting safety blocks as failures.

Claude Fable 5.1 and Claude Mythos 5.1 System Card · Table8.1.A;8.15.6 · reviewed 2026-09-24

Zapier private held-out leaderboard; simulated business workflows; every deterministic assertion must pass; max effort.

Provider-published lab self-report from the Claude Opus 5.5 system card (SHA256 7311c9c6bbb16d012f1c12c7418b05949fcf7ae3e30d2c40f22050074b2a7378). Not an independent board. Launch grid shows 40.0%. Launch footnote 2 says Zapier ran these without fallback models and counted safeguard interventions as failures.

Comparison limit: Provider-published lab self-report. Shown as a labeled claim and not admitted as a matched board comparison.

Claude Opus 5.5 System Card · Table 8.1.A; section 8.14.6 · reviewed 2026-09-22