Polaris-OSS-3B-Base
Model ID: purposebyoriento/polaris-oss-3b-base
A 3B parameter open-source instruction-tuned language model designed for structured explanation generation within deterministic systems. Optimized for transparency, auditability, and controlled output in institutional B2B contexts.
Model Description
Polaris-OSS-3B-Base is a specialized foundation model that transforms structured data signals into human-readable explanations. It is designed to operate as a controlled transparency layer, not as an autonomous decision-making agent.
Key Characteristics
- Size: ~3 billion parameters
- Task: Structured explanation generation from JSON inputs
- Output Style: Deterministic, factual, neutral tone
- Context Window: Dependent on base architecture (typically 2K-8K tokens)
- Deployment: Optimized for 4-bit quantization
Architecture Role
Rule-Based Matching Engine
β
Confidence Layer
β
Polaris-OSS-3B (Explanation Adapter)
β
Validation Layer
β
User Interface
Polaris does not perform:
- Ranking or filtering decisions
- Eligibility determinations
- Autonomous personalization
- User profiling or diagnostics
Intended Uses
Primary Use Case: Explanation Generation
Input:
- Structured user attributes (interests, availability, preferences)
- Opportunity metadata (type, location, cost, timing)
- Pre-computed matching signals from rule-based engine
Output:
- 2-4 sentence explanations of why an opportunity was matched
- Attribute-aligned reasoning
- No hallucinated claims or invented attributes
Example:
Input:
{
"user_attributes": {
"interests": ["STEM", "leadership"],
"availability": "summer",
"cost_preference": "low"
},
"opportunity": {
"title": "Youth Robotics Camp",
"type": "STEM workshop",
"season": "summer",
"cost": "free"
},
"match_signals": ["interest_alignment", "time_fit", "cost_fit"]
}
Output:
"This opportunity aligns with your interest in STEM and leadership. It takes
place during your available time period and fits your cost preference."
Secondary Use Cases (Future Extensions)
- Opportunity content summarization
- Controlled reflection prompt generation
- Content normalization during data ingestion
- Light semantic interpretation of structured fields
Out-of-Scope Use
β Do not use for:
- Autonomous decision-making or ranking
- Diagnostic labeling of users
- Open-ended creative writing
- Medical, legal, or financial advice
- Any use case requiring multi-step reasoning without validation
- Unsupervised personalization
Training Details
Fine-Tuning Strategy
Polaris-OSS-3B-Base serves as a frozen backbone with task-specific LoRA adapters:
1. Explanation Adapter
ID: polaris-oss-3b-explain-lora-v1
Task: Transform structured matching signals into human-readable explanations
Training Data Schema:
- Input: JSON with user attributes + opportunity metadata
- Output: 2-4 sentence factual explanation
- Format: Instruction-following pairs
2. STARR Adapter (Optional)
ID: starr-oss-3b-clarify-lora-v1
Task: Generate single clarification questions from ambiguous user inputs
Training Data Schema:
- Input: Incomplete or ambiguous user response
- Output: One specific clarifying question
- Constraint: No multi-question chaining
Guardrails
All adapters enforce:
Strict Prompt Templates
- "Use only provided data"
- "Do not invent attributes"
- "Do not label the user"
Output Validation
- Regex-based attribute verification
- Length constraints (50-200 tokens)
- Fact alignment checks against input
Determinism Controls
- Low temperature (0.3-0.5)
- Limited max tokens (100)
- Constrained decoding strategies
Technical Specifications
| Parameter | Value |
|---|---|
| Parameters | ~3 billion |
| Precision | FP16/BF16 native, INT4 recommended |
| Hardware | GPU preferred (NVIDIA T4+), CPU possible |
| Inference Latency | <100ms (quantized, GPU) |
| Memory Footprint | ~2GB (4-bit), ~6GB (FP16) |
| Fine-tuning Method | LoRA (rank 8-16) |
| Training Framework | Compatible with HuggingFace Transformers |
Deployment Recommendations
- Production: 4-bit GPTQ/AWQ quantization
- Development: FP16 for fine-tuning
- Batch Size: 1-8 for real-time inference
- Context Length: Keep under 512 tokens for optimal latency
Evaluation
Performance Characteristics
Strengths β
- Fast inference (<100ms)
- Low infrastructure cost
- Sufficient for structured transformation tasks
- Scalable for early-stage B2B deployment
- Deterministic output with proper guardrails
Limitations β οΈ
- Weaker multi-factor reasoning compared to 7B models
- Higher hallucination probability without strict validation
- Less nuanced language generation
- Limited long-term context handling
Benchmarks
Note: Standard NLP benchmarks (MMLU, HellaSwag) are less relevant for this specialized use case. Task-specific evaluation focuses on:
- Factual Accuracy: 95%+ (outputs contain only input-provided attributes)
- Attribute Coverage: 90%+ (mentions all relevant matching signals)
- Length Compliance: 98%+ (stays within 2-4 sentence constraint)
- Tone Neutrality: Manual review (institutional appropriateness)
Ethical Considerations
Data Governance
Polaris operates under strict data minimization:
- β Receives structured attributes only
- β No access to full user history
- β No unnecessary personal identifiers
- β No external data retrieval or browsing
Transparency
All explanations are:
- Auditable (traceable to input data)
- Non-diagnostic (no psychological labeling)
- Non-profiling (no inferred characteristics)
- Legally defensible (based on stated preferences)
Bias Mitigation
- Training data reviewed for demographic balance
- Outputs validated for neutral language
- No subjective value judgments in explanations
- Regular audits for unintended stereotyping
How to Get Started
Installation
pip install transformers accelerate bitsandbytes
Basic Usage (FP16)
from transformers import AutoModelForCausalLM, AutoTokenizer
model_id = "purposebyoriento/polaris-oss-3b-base"
tokenizer = AutoTokenizer.from_pretrained(model_id)
model = AutoModelForCausalLM.from_pretrained(
model_id,
torch_dtype="auto",
device_map="auto"
)
prompt = """Given the following data, explain why this opportunity matches:
User: interests in [STEM, leadership], available [summer], prefers [low-cost]
Opportunity: Youth Robotics Camp, type [STEM workshop], season [summer], cost [free]
Match signals: interest_alignment, time_fit, cost_fit
Explanation:"""
inputs = tokenizer(prompt, return_tensors="pt").to(model.device)
outputs = model.generate(**inputs, max_new_tokens=100, temperature=0.4)
print(tokenizer.decode(outputs[0], skip_special_tokens=True))
Quantized Inference (4-bit)
from transformers import AutoModelForCausalLM, BitsAndBytesConfig
quantization_config = BitsAndBytesConfig(
load_in_4bit=True,
bnb_4bit_compute_dtype="float16"
)
model = AutoModelForCausalLM.from_pretrained(
"purposebyoriento/polaris-oss-3b-base",
quantization_config=quantization_config,
device_map="auto"
)
Fine-Tuning with LoRA
from peft import LoraConfig, get_peft_model
lora_config = LoraConfig(
r=16,
lora_alpha=32,
target_modules=["q_proj", "v_proj"],
lora_dropout=0.05,
bias="none",
task_type="CAUSAL_LM"
)
model = get_peft_model(model, lora_config)
# Proceed with standard Trainer API
Upgrade Path
Polaris-OSS-3B-Base is designed for cost-efficient deployment in early stages:
| Phase | Model | Use Case |
|---|---|---|
| Phase 1 | 3B (Current) | Explanation generation, basic clarity |
| Phase 2 | 7B | Improved multi-factor reasoning |
| Phase 3 | Custom Distilled | Proprietary optimization |
The naming convention and adapter architecture support seamless upgrades without system redesign.
Citation
@misc{polaris-oss-3b-2026,
title={Polaris-OSS-3B-Base: A Structured Explanation Model for Deterministic Matching Systems},
author={Purpose by Oriento},
year={2026},
publisher={HuggingFace},
howpublished={\url{https://huggingface.co/purposebyoriento/polaris-oss-3b-base}}
}
Model Card Authors
Purpose by Oriento Team
For questions, issues, or collaboration:
- Organization: Purpose by Oriento
- Contact: [Insert contact information]
- Documentation: See
SYSTEM_SPECIFICATION.mdfor architectural context
License
Apache 2.0
See LICENSE file for full terms.
Acknowledgments
This model is part of the Oriento platform for structured youth opportunity matching. It reflects a commitment to:
- Transparent AI in institutional contexts
- Deterministic, auditable systems
- User agency and preference respect
- B2B trust and legal defensibility
Polaris enhances clarity β it does not control matching logic.
Last Updated: February 2026
Model Version: v1.0.0-base