LFM2.5-1.2B-RLCD (Certa)

A System-One calibrated decision model: given a state and typed questions, it returns typed answers with calibrated probabilities in a single forward pass — no text generation, no parsing. Runs with the open-source certa library (pip install certa); training recipe summarized below.

• Base: LiquidAI/LFM2.5-1.2B-Base
• Task: Choice (pick one of ≤26 options), Score (ordered level), Noul (yes/no probability)
• In-distribution test: 0.766 accuracy · 0.319 Brier · 0.043 ECE · 0.079 AURC
• Latency: ≈ 14 ms per multi-question decision (warm, L40S)
• API: compatible with TypeSafe.ai's Jev POST /v1/systemone

Usage

pip install certa

from certa.engine import ModelEngine
from certa.client import choice, score, verify

engine = ModelEngine("goutam/LFM2.5-1.2B-RLCD")

resp = engine.decide(
    "I was double-charged and support has ignored me for three days.",
    {
        "team":   choice("Route this ticket", {"billing": "charges", "technical": "bugs", "sales": "pricing"}),
        "anger":  score("How angry is the customer?", ["calm", "annoyed", "furious"]),
        "urgent": verify("Does the message convey urgency?"),
    },
)
print(resp.answers["team"].choice, resp.answers["team"].confidence)   # billing 0.79
print(resp.answers["anger"].score)                                    # 1.44 (0–2)
print(resp.answers["urgent"].noul)                                    # 0.78

To serve the Jev-compatible HTTP API:

CERTA_CHECKPOINT=goutam/LFM2.5-1.2B-RLCD pip install 'certa[serve]' && python -m certa --port 8000

Training

1. Supervised warm start on 12k labelled rows from goutam/rlcd-decision-atlas: focal (γ=2) + multiclass Brier over the option-token logits.
2. RLCD refinement (Reinforcement Learning for Calibrated Decisions) on the remaining ~519k rows: REINFORCE in a single-step bandit setup (sample one option, one scalar reward), reward r = correct − p(action) (RPS partial-credit for ordinal questions), RLOO (leave-one-out) baseline, light KL to the supervised reference.

Evaluation

Split	Accuracy	Brier ↓	ECE ↓	AURC ↓
Test (in-distribution)	0.766	0.319	0.043	0.079
Validation	0.772	0.333	0.054	—
Holdout (unseen sources)	0.458	0.678	0.157	0.395

Multiclass-sum Brier (range 0–2), top-label 15-bin ECE. Selective prediction: acting only when the top probability ≥ 0.9 covers ≈ 39% of cases at ≈ 2.9% error — a calibrated confidence gate for act-vs-escalate routing.

Intended use & limitations

Use for: fast calibrated routing, triage, classification, and grading over text where you need a probability you can threshold — and to abstain/escalate on low-confidence cases.

Limitations:

• Out-of-distribution: weak (~0.46 accuracy) on entirely unseen source types — broaden training coverage for new domains, and re-check calibration on yours.
• ≤ 26 options per Choice (single-letter decode); larger sets are rejected.
• Trained on English-leaning text sources; non-text / non-English inputs are unsupported.

License

Weights are released under the LFM Open License v1.0 (inherited from the base model). Accompanying code (certa, certa-rlcd) is Apache-2.0. Not affiliated with TypeSafe.ai.