Diagnose the MPC stall in the log at $ARGUMENTS (a localnet/validator log file, or a CI run ID whose localnet-logs artifact should be downloaded first).

Execute dev-docs/playbooks/mpc-stall-postmortem.md — the checks are ORDERED and each either identifies the stall class or eliminates it; do not skip ahead, and do not stop at the first anomaly without finishing the cheap checks (co-resident bugs have occurred):

Timeline anchors (highest epoch, lock/EOP lines, last quorum).
Malicious conviction FIRST (recognized itself as malicious).
Started-vs-completed computation balance per validator.
Epoch-entry key-gap warns (Adopted network key epoch does not match).
Chain counters: completed vs frozen lock target (over/undershoot).
Which pipeline stages still flow (votes / admission / serving / sync).
Trace ONE stuck session end-to-end across all validators.