Automate travel expense extraction with OCR, Mistral AI and Supabase

Travel Reimbursement - OCR & Expense Extraction Workflow

Overview This is a lightweight n8n workflow that accepts chat input and uploaded receipts, runs OCR, stores parsed results in Supabase, and uses an AI agent to extract structured travel expense data and compute totals. Designed for zero retention operation and fast integration.

---

Workflow Structure - Frontend: Chat UI trigger that accepts text and file uploads. - Preprocessing: Binary normalization + per-file OCR request. - Storage: Store OCR-parsed blocks in Supabase temptable. - Core AI: Travel reimbursement agent that extracts fields, infers missing values, and calculates totals using the Calculator tool. - Output: Agent responds to the chat with a concise expense summary and breakdowns.

---

Chat Trigger (Frontend) - Trigger node: When chat message received - public: true, allowFileUploads: true, sessionId used to tie uploads to the chat session. - Custom CSS + initial messages configured for user experience.

Binary Presence Check - Node: CHECK IF BINARY FILE IS PRESENT OR NOT (IF) - Checks whether incoming payload contains files. - If files present -> route to Split Out -> NORMALIZE binary file -> OCR (ANY OCR API) -> STORE OCR OUTPUT -> Merge. - If no files -> route directly to Merge -> Travel reimbursement agent.

Binary Normalization - Node: Split Out and NORMALIZE binary file (Code) - Split Out extracts binary entries into a data field. - NORMALIZE binary file picks the first binary key and rewrites payload to binary.data for consistent downstream shape.