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Orion Investigation — S42 engine_requested_halt

To: Orion (he/him) From: Vesper (she/her) CC: Katja (Captain), Atlas (he/him) Date: 2026-04-21 Type: Investigation only — no code, no branch pre-creation

What Happened

S42 ran 8.4 minutes of a 30-minute live session and halted early with:

HALT REASON: engine_requested_halt
Ticks executed: 89
Elapsed (s): 501.81

Anchor saturation guard had threshold conditions met: - mean anchor error: -6.95 bps (threshold: ≥ 6–8 bps abs) - |err| > 5 bps prevalence: 78.4% (threshold: ≥ 40%) - Persisted well beyond 20–30 tick trigger window

The guard should have entered DEGRADED (cancel all, stop quoting, continue loop). DEGRADED is designed to be a recoverable state — the loop continues. It should not halt.

The session halted. We need to know why.

Investigation Questions

Q1 — What triggered engine_requested_halt? Pull the S42 session log (DB or log file). Find the exact log line or guard condition that set the halt reason to engine_requested_halt. Was it: - The anchor saturation guard explicitly requesting a halt after N ticks in DEGRADED? - An uncaught exception that fell through to the halt handler? - A different guard (directional drift, inventory corridor) triggering concurrently? - Something else?

Q2 — Is there a DEGRADED→HALT escalation path in the anchor saturation guard? Check _evaluate_anchor_saturation_guard in main_loop.py. Does the current implementation include any escalation from DEGRADED to halt (e.g., after remaining in DEGRADED for N ticks without recovery)? If yes, is this intentional per spec or unintended?

Q3 — What does engine_requested_halt mean in main_loop.py? Find all call sites that set or trigger engine_requested_halt in the halt reason. List them. Which one fired in S42?

Q4 — Was the halt protective or erroneous? Given findings from Q1–Q3: was the halt the correct behavior for this market regime, or is it a bug that should be fixed before S43?

Constraints

  • Investigation only — no code changes, no branch pre-creation
  • Report findings before any fix is proposed
  • If a fix is warranted, Vesper will scope the branch

Deliverable

Findings report: answer Q1–Q4. Quote the relevant log lines and code. Flag explicitly if this is a bug vs. intentional behavior. Vesper and Atlas will decide next steps.

— Vesper