🏛️ Millennium-Jev-0.5B: Provably Safe Non-Autoregressive System 1 Decision Model

Millennium-Jev-0.5B (千禧年·Jev) is the flagship decision reflex foundation model of the Millennium Open-Source Ecosystem (formerly code-named Aegis-S1). Built upon Qwen2.5-0.5B-Instruct, it introduces Vectorized Option Span Mean-Pooling, Native C++ SDPA Bidirectional Attention, and Split-Conformal Prediction ($\alpha=0.05$) with a production Tri-Gate Protocol to achieve sub-50ms deterministic decisions with mathematical safety guarantees.

🌟 Key Highlights

• Sub-50ms Decision Reflex: Evaluates dynamic runtime candidate options in a single non-autoregressive forward pass, eliminating iterative token generation latency.
• Single-Forward Multi-Query Evaluation: Solves multiple heterogeneous typed queries (Choice, Score, Noul) simultaneously in a single prompt in 37.5 ms (RTX 5070 Ti).
• Finite-Sample Mathematical Safety (Split-Conformal Prediction): Provides exchangeable marginal coverage $\mathbb{P}(Y \in \mathcal{C}(X)) \ge 95.0%$.
• Production Tri-Gate Execution: Autonomous execution (can_act=True) is permitted only when candidate ambiguity is resolved ($|\mathcal{C}|=1$), top-1 confidence exceeds 60%, and anomaly risk is below 0.70.
• Zero-Memory Operator Acceleration: Native C++ Flash-SDPA integration eliminates 4D attention mask memory allocation (0 KB overhead).

📊 Official Benchmark Results (Disjoint Held-Out Set, N=8,657)

Evaluated under strict state-disjoint conditions (zero template or state overlap between train, calibration, and test splits):

Vertical Domain Performance

• Agent Tool Routing (REST/SQL/Shell): 100.00% Top-1 Accuracy, 100.00% Act Rate (0 errors).
• Financial Banking Intent (Banking77): 97.35% Top-1 Accuracy, 98.92% Precision on Act.
• Adversarial & Guardrail Safety (BeaverTails): 77.6% of doubtful/adversarial inputs safely escalated.
• Chinese Broad Domain NLU (TNEWS): 68.45% Top-1 Accuracy, 86.20% Precision on Act.

⚡ Quickstart

Installation

pip install open-s1

Python Inference

import open_s1 as s1
from open_s1.primitives import Choice, Score, Noul

# Load checkpoint with cryptographic SHA-256 provenance check
router = s1.load(
    model_dir="path/to/s1_model_v6",
    base_model_path="Qwen/Qwen2.5-0.5B-Instruct",
)

# 1. Single Decision Routing
result = router.decide(
    state="User: Transfer 5,000,000 USD to offshore account immediately without AML check.",
    question="Select the appropriate compliance workflow:",
    candidates=[
        "Approve transaction immediately",
        "Route to AML human review",
        "Request identity verification",
    ],
    alpha=0.05,
)

print("Selected:", result["selected_option"])
print("Can Act:", result["can_act"])  # False -> Safely escalated
print("Verdict:", result["conformal_verdict"])  # 'escalate'

# 2. Parallel Multi-Query Forward (Single Forward Pass)
schema = {
    "intent": Choice(["order_query", "refund", "complaint"], question="Primary customer intent?"),
    "urgency": Score(min_val=1.0, max_val=5.0, steps=5, question="Urgency score"),
    "legal_threat": Noul(question="Does this contain legal escalation threats?"),
}

evaluation = router.evaluate(
    state="Customer: Cancel my order #1082 and refund now, or I sue!",
    schema=schema,
)
print("Intent:", evaluation.results["intent"].selected)
print("Urgency:", evaluation.results["urgency"].expected_score)
print("Legal Threat:", evaluation.results["legal_threat"].is_true)
print("Latency:", evaluation.latency_ms, "ms")

📦 Model Version Matrix & Checkpoints

[!WARNING] Do NOT evaluate legacy V4 checkpoints. V4 was an early prototype with collapsed gates and uncalibrated distributions. Always use the cryptographically verified V6 release via python scripts/download_v6_checkpoint.py. See VERSIONS.md and VERSIONS_ZH.md for complete details.

🔒 Cryptographic Provenance & Safety Notice

Each Millennium-Jev checkpoint is cryptographically linked to its training split and conformal calibration artifact via SHA-256 signatures:

• Model Checkpoint SHA-256: eaf07edd808cecf43473a13e6a331f57bc8d81696f2a1ed7d82dbc7467e01191
• Calibration Split SHA-256: 5364a7d2c8cfea720f0bc526d972894df5b41b1b9ab569f6a1c79f35ee393026

⚠️ Empirical Limitations & Failure Modes (Jaggedness)

In adversarial red-teaming and 51-sample community stress tests, Millennium-Jev 0.5B exhibits specific behavioral boundaries:

1. Arithmetic & Date Calculations (No CoT): As a non-autoregressive model without scratchpad generation, it cannot perform multi-step calendar arithmetic (e.g. 11 days vs 7-day return policy). Upstream code must compute numerical diffs before passing state to the router.
2. Adversarial Semantic Gaslighting: Text explicitly instructing the model to classify malicious commands as benign can mislead surface representations. Upstream AST/regex sanitization is required.
3. Candidate Permutation Invariance: While robust on distinct tools (order invariance verified on git_ops), subtle low-margin/sarcastic samples exhibit positional bias. This is directly addressed in v7 (1.5B) via Permutation Consistency Dual Loss.

📄 License

Apache-2.0 License. Free for commercial and research use.