Level 1 Case StudyAI Systems / Jun 2025
Spendora - Conversational AI for Expense Insights
I built an LLM-powered conversational AI assistant that provides personalized expense insights using retrieval-augmented generation and tool-based reasoning.
No published metric yet
01
TL;DR
- I built an LLM-powered conversational AI assistant that provides personalized expense insights using retrieval-augmented generation and tool-based reasoning.
- Result metrics are not published yet.
02
Problem
- How can users get intelligent insights about their spending habits through natural conversation? Anyone wanting AI-powered financial analysis without manual data analysis. Most expense tracking tools lack conversational intelligence and context-aware recommendations.
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My Role
- personal build with end-to-end ownership
- Problem framing: How can users get intelligent insights about their spending habits through natural conversation?
- Architecture: LangChain conversational agents with memory management
- Implementation: Custom financial data toolchains, vector embeddings for RAG
- Evaluation: metrics not published yet
- Before: Most expense tracking tools lack conversational intelligence and context-aware recommendations
- Personally designed: Used LangChain for agent orchestration because Simplifies memory management and tool-use patterns for conversational AI; Implemented RAG with custom toolchains because Enables grounding in actual financial data without fine-tuning
- Others owned: No separate collaborator-owned subsystem is published in the source data.
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Constraints
- Built Jun 2025 (personal). Limited time, focus on LLM integration quality.
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Architecture
- Input: Natural language queries about expenses
- Backend: LangChain conversational agents with memory management
- Data & storage: Custom financial data toolchains, vector embeddings for RAG
- External APIs: HuggingFace models (Mistral, Gemma), LangChain framework
- Output: Conversational interface with context-aware financial recommendations
LangChain conversational agents with memory management; Custom financial data toolchains, vector embeddings for RAG; Conversational interface with context-aware financial recommendations
- input 01Input
Natural language queries about expenses
- process 02Backendinput ->
LangChain conversational agents with memory management
- storage 03Data / storagebackend ->
Custom financial data toolchains, vector embeddings for RAG
- external 04External APIsbackend ->
HuggingFace models (Mistral, Gemma), LangChain framework
- output 05Outputstorage ->external ->
Conversational interface with context-aware financial recommendations
Routes
- Input -> Backend
- Backend -> Data / storage
- Backend -> External APIs
- Data / storage -> Output
- External APIs -> Output
06
Key Technical Decisions
- Used LangChain for agent orchestration
- Implemented RAG with custom toolchains
07
Implementation
- Input layer: Natural language queries about expenses
- Core system: LangChain conversational agents with memory management
- Data layer: Custom financial data toolchains, vector embeddings for RAG
- External boundary: HuggingFace models (Mistral, Gemma), LangChain framework
- User output: Conversational interface with context-aware financial recommendations
08
What Broke / What Didn't Work
- Rejected: Building custom conversation loop. Chosen path: Used LangChain for agent orchestration.
- Rejected: Fine-tuned LLM on expense data. Chosen path: Implemented RAG with custom toolchains.
- RAG adds latency for retrieval but improves accuracy over hallucination-prone base models
- Multiple toolchains provide flexibility but increase complexity
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Results
- No headline result metric is published yet; this page keeps unsupported claims out of the story.
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What I'd Change Now
- Add real-time transaction integration
- Implement budget forecasting
- Support multi-currency analysis
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Stack
- HuggingFace (Mistral, Gemma models)
- LangChain
- Python
- Vector embeddings
12
Links
- Source docs: 2-projects.json
Deep dive prompts
Ask me about the trade-offs.
- Why this architecture boundary exists: LangChain conversational agents with memory management
- How I evaluated how I would measure the next version
- The hardest tradeoff: RAG adds latency for retrieval but improves accuracy over hallucination-prone base models
- What I would change next: Add real-time transaction integration