How to Add Tamper-Evident Audit Trails to Your LangChain Agent

Your LangChain agent calls tools. It searches the web, reads files, queries databases, calls APIs. But can you prove what it did? Logs capture what happened. Cryptographic receipts prove it. The difference matters when an auditor, a customer, or a regulator asks "show me exactly what the agent did and prove it wasn't altered after the fact." This tutorial adds Ed25519-signed, hash-chained audit trails to a LangChain agent in under 5 minutes. No external service, no API keys, no infrastructure. E