How AVELIN Works
Technical Architecture Overview
AVELIN implements API-level Mixture-of-Experts — a specialist selection and fusion layer that automatically optimizes every request for cost, quality, and reliability. This page explains the technical flow from request to response.
The 6-Stage Request Flow
User Request
↓
┌─────────────────────────────────────────────────────────┐
│ Stage 1: Semantic Router (50ms) │
│ - Classifies task type: code, reasoning, chat, etc. │
│ - Embeds request using semantic transformer │
│ - KNN classifier selects optimal model family │
└─────────────────────────────────────────────────────────┘
↓
┌─────────────────────────────────────────────────────────┐
│ Stage 2: Cross-Model MoE Classifier │
│ - Considers: cost, latency, quality, availability │
│ - Selects specific model tier (ultra/pro/fast) │
│ - Can route to multiple models in parallel (fusion) │
└─────────────────────────────────────────────────────────┘
↓
┌─────────────────────────────────────────────────────────┐
│ Stage 3: Model Fusion Layer (if enabled) │
│ - Queries multiple frontier models in parallel │
│ - Averages token probabilities or votes on answers │
│ - Cross-verifies responses to reduce hallucinations │
└─────────────────────────────────────────────────────────┘
↓
┌─────────────────────────────────────────────────────────┐
│ Stage 4: Confidence Scoring │
│ - Evaluates model confidence in response │
│ - High confidence (>0.8): return response │
│ - Low confidence (<0.8): escalate to premium model │
└─────────────────────────────────────────────────────────┘
↓
┌─────────────────────────────────────────────────────────┐
│ Stage 5: Response Transformation │
│ - Sanitizes reasoning content (chain-of-thought) │
│ - Applies AVELIN branding │
│ - Strips provider identifiers │
└─────────────────────────────────────────────────────────┘
↓
┌─────────────────────────────────────────────────────────┐
│ Stage 6: Continuous Evaluation (background) │
│ - Benchmarks all providers hourly │
│ - Tracks: accuracy, latency, cost per task type │
│ - Auto-updates selection weights based on performance │
└─────────────────────────────────────────────────────────┘
↓
Response Returned (3.5s average total latency)
Stage 1: Semantic Routing (50ms Latency)
AVELIN's semantic router classifies every incoming request before it reaches a model. This is the key differentiator from basic multi-provider proxies.
How it works:
- Request text is embedded using a lightweight semantic transformer model
- KNN classifier matches to task type based on training data
- Optimal model family is selected
Task classification examples:
Impact:
- 68% of requests routed to cost-efficient models
- 23% quality improvement on specialized tasks
- 50ms classification latency (negligible vs 2-5s model response)
Training data: Built from millions of real production requests, continuously updated.
Stage 2: Intelligent Model Selection
Once the task type is classified, AVELIN's router selects the optimal model tier within that family.
Selection criteria:
- Cost: Prefer cheaper models for simple tasks
- Latency: Consider time-to-first-token requirements
- Quality: Match model capability to task complexity
- Availability: Route away from degraded providers
- Context length: Ensure model can handle request size
Model tier mapping:
Stage 3: Multi-Model Fusion (Optional)
For critical requests, AVELIN can query multiple frontier models in parallel and aggregate their responses.
Aggregation strategies:
-
Weighted token probability averaging
- Combine probability distributions from multiple models
- Higher weight to models with better benchmark scores
- Produces "average" response that's often better than any single model
-
Voting
- Each model generates independent response
- Pick most common answer (majority vote)
- Effective for factual questions
-
Synthesis
- Use a meta-model to merge responses
- Extract best parts from each
- Most expensive but highest quality
Impact:
- 17% hallucination reduction through cross-verification
- Stronger synthesis on ambiguous tasks
- Higher confidence in critical responses
When enabled: Automatically for avelin-ultra on high-stakes requests, or manually via API parameter.
Stage 4: Confidence-Based Cascading
AVELIN doesn't always use the most expensive model. It starts with cost-efficient models and escalates only when needed.
The cascading flow:
Request arrives
↓
avelin-fast tries (cost-efficient tier, $0.0005/request)
↓
Confidence score calculated (0.0 to 1.0)
↓
┌──────────────────────────────────────┐
│ If confidence > 0.8: │
│ Return response (cheap path) │
│ │
│ If confidence < 0.8: │
│ Escalate to avelin-ultra │
│ ($0.004/request) │
│ Return premium response │
└──────────────────────────────────────┘
Impact:
- up to 85% cost savings on routine workloads
- Premium quality preserved for complex tasks
- Automatic optimization based on model uncertainty
Escalation rate: ~20% of requests escalate (80% handled by efficient models).
Stage 5: Response Transformation
Before returning the response to the user, AVELIN applies several transformations:
- Reasoning sanitization: Strips chain-of-thought that might reveal backend providers
- Branding: Ensures consistent AVELIN identity
- Error handling: Sanitizes error messages to prevent information leakage
- Format normalization: Ensures consistent API response format
Stage 6: Continuous Evaluation (Background)
AVELIN continuously benchmarks all providers and automatically updates selection weights.
Evaluation process:
- Every hour, run benchmark suite on all providers
- Track: accuracy, latency, cost, availability per task type
- Update selection weights based on performance
- Deploy updated weights (no restart required)
Real-world results (last 90 days):
- Routing weights updated 312 times
- 8% quality improvement over baseline
- 12% cost decrease as cheaper models improved
- Automatic failover when providers degraded
Benchmark categories:
- Coding: SWE-bench, HumanEval, MBPP
- Reasoning: MMLU, GPQA, GSM8K
- Agentic: TauBench, AgentBench
- Multilingual: Various language tasks
Performance Characteristics
Latency breakdown (median):
- Prompt-vector classifier: 50ms
- Model selection: 10ms
- Model inference: 2,500ms (varies by provider)
- Response transformation: 20ms
- Total: ~2.6s average
Streaming throughput: 18.8 chunks/sec
Time-to-first-token: 1.6s median
Reliability:
- 99.97% uptime (multi-provider fallback)
- 0.3s average failover time
- 0 data loss incidents in 12 months
Cost Optimization
Average cost per request: $0.003 (varies by model tier)
Cost breakdown by specialist selection:
- 68% requests → efficient models ($0.0002-$0.0005)
- 20% requests → balanced models ($0.001-$0.002)
- 12% requests → premium models ($0.002-$0.007)
vs alternatives:
- vs single-provider direct access: 42% cheaper
- vs always-premium selection: up to 85% cheaper
- vs manual model selection: 23% better quality on specialized tasks
Comparison to Traditional Approaches
Technical Specifications
Supported protocols:
- OpenAI-compatible API (chat completions, embeddings)
- Function calling / tool use
- Streaming responses
- Batch processing
Model families:
- Intelligence: ultra, pro, fast
- Coding: coding, coding-plus, coding-architect
- Agentic: agentic-high, agentic, agentic-fast
- Utility: embeddings (bge-m3), transcription (whisper), image generation
Infrastructure:
- Kubernetes-based (k3s cluster)
- Multi-region deployment (Hetzner, OVHcloud)
- Horizontal pod autoscaling (3-10 replicas)
- Redis for distributed state
- PostgreSQL for persistence
Security:
- TLS encryption in transit
- API key authentication
- Request/response sanitization
- PII stripping (configurable)
- Zero data retention policy (configurable)
Getting Started
AVELIN is OpenAI-compatible. Switch in 5 minutes:
from openai import OpenAI client = OpenAI( base_url="https://api.avelin.ai/v1", api_key="your-avelin-api-key" ) response = client.chat.completions.create( model="avelin-pro", # or ultra, fast, coding, etc. messages=[{"role": "user", "content": "Hello!"}] )
No code changes needed if you're already using the OpenAI SDK. AVELIN handles all the specialist selection, fusion, and optimization automatically using its prompt-vector classifier with 90% accuracy.