Production-Grade Document Intelligence & Extraction Engine
An enterprise-grade multi-agent document processing pipeline built to ingest, classify, and extract structured data from heterogeneous documents at massive scale. Combining OCR pipelines, tiered model routing (SLMs & LLMs), DSPy prompt optimization, and PostgreSQL pgvector hybrid RAG—delivered as containerized microservices across Azure and GCP.
Reduced token consumption through SLM routing and DSPy compiled signatures.
Extraction latency achieved with async parallel nodes and fast OCR pre-filters.
Deterministic JSON schema enforcement with Pydantic and self-critique loops.
Multi-Stage Document Ingestion, Routing & Storage Pipeline
The platform processes heterogeneous document formats (Identity Cards, Passports, Financial Records, Legal Certifications, Invoices) through a 5-stage decoupled agentic mesh. Incoming payloads are ingested via secure REST APIs, classified by fast visual-textual models, routed dynamically, normalized via DSPy-compiled prompts, and vectorized into PostgreSQL.
Ingestion & OCR
Accepts PDFs, scans, and multi-page images. Applies layout analysis, deskewing, and fast OCR text layer extraction.
Classifier & Router
LangGraph routing agent classifies document typology and confidence score to dispatch tasks to appropriate model tiers.
Tiered Extraction
Lightweight SLMs (Ollama) handle standard formats. Complex semi-structured docs escalate to DSPy-compiled frontier LLMs.
Storage & Hybrid RAG
Persists structured tables to relational PostgreSQL schema while vectorizing full text and FAQ semantic chunks in pgvector.
Enterprise APIs
Exposes low-latency OpenAPI endpoints consumed by CRMs, ERPs, client portals, and automated robotic process workflows.
Technical ArchitectureView Mermaid Graph SpecificationToggle Code
graph LR
subgraph Ingestion ["Stage 1: Multi-Doc Ingestion"]
A[Raw Documents: PDF / Image / Scan] --> B[OCR & Visual Layout Engine]
end
subgraph Classification ["Stage 2: Agentic Routing"]
B --> C[Document Classification Agent]
C -->|High Structure: ID / Invoices| D[Tier 1: On-Prem SLM (Ollama)]
C -->|Unstructured: Complex Certs / Text| E[Tier 2: Frontier LLM + DSPy]
end
subgraph Optimization ["Stage 3: Optimization & Guardrails"]
D & E --> F[DSPy Teleprompter Validation]
F --> G[Langfuse Observability & Token Tracker]
G --> H{Pydantic Schema Gate}
H -->|Fail Assertion| C
H -->|Pass Assertion| I[Normalized Output]
end
subgraph Persistence ["Stage 4: Storage & RAG"]
I --> J[(PostgreSQL Relational DB)]
I --> K[(pgvector Embedding Store)]
K --> L[Semantic Search & FAQ RAG Engine]
end
subgraph Distribution ["Stage 5: Agents as a Service"]
J & L --> M[FastAPI Gateway / Docker Container]
M --> N[Enterprise ERP / CRM / Upstream APIs]
endScaling AI Processing Without Escalating Cloud Spend
When building prototype document extractors, frontier models deliver impressive zero-shot results. However, when moving from a proof-of-concept into enterprise production—processing hundreds of thousands of multi-page documents monthly—uncontrolled LLM calls create unsustainable cloud bills and unpredictable latency.
As the technical lead, the challenge was to eliminate three classic enterprise failure modes:
- Runaway Token Spend: Bloated document contexts and raw OCR outputs driving up inference costs unnecessarily.
- Latency Bottlenecks: Forcing simple deterministic forms through slow cloud reasoning models instead of nimble on-prem SLMs.
- Schema Drift & Risk: Hallucinations in edge-case documents causing downstream failures in core ERP/CRM databases.
Algorithmic Prompt Optimization via DSPy
Instead of manually editing fragile prompts for dozens of document templates, the system leverages DSPy to programmatically compile and optimize master prompts against synthetic and curated ground-truth datasets.
Strict Typed Signatures
Replaced fragile textual system prompts with declarative typed signatures (`dspy.Signature`). The system deterministically extracts only required fields without conversational bloat.
Automated Prompt Search
DSPy automated few-shot compilation finds the mathematically optimal demonstration examples that maximize accuracy across messy, edge-case document layouts.
Tiered Model Architecture
Clean, standardized documents execute instantly on lightweight local models, reserving expensive cloud reasoning models strictly for complex or low-confidence inputs.
PostgreSQL, pgvector & Multi-Index Hybrid RAG
Processed document intelligence serves dual purposes: structured transactional queries and semantic unstructured retrieval. The data layer bridges both paradigms within a single unified PostgreSQL engine.
Relational Entity Database
Strict relational tables store validated demographic fields, certificate serials, tax IDs, and validation timestamps with ACID guarantees, foreign keys, and indexes for instant SQL lookup.
pgvector & FAQ Hybrid RAG
Full document clauses and dynamic FAQ indices are chunked, embedded, and stored with HNSW indexes in pgvector. Combines BM25 lexical search with vector cosine similarity for pinpoint question-answering.
Containerized Cloud Microservices & Enterprise APIs
The entire agentic system is packaged into modular, containerized Docker microservices exposed as secure REST and async webhook APIs. Designed for multi-cloud deployments across Azure Container Apps and Google Cloud Platform (GCP Cloud Run / GKE).
Lightweight multi-stage builds with CPU/GPU runtime support.
Autoscaling from 0 to N instances based on message queue depth.
Seamless ingestion hooks for enterprise CRMs, ERPs & portals.