Sigill — AI Conversation Timestamper

Cryptographically timestamps every AI conversation turn using RFC 3161 via Sigill.

Sigill turns your AI conversations into verifiable evidence. Every completed conversation turn on claude.ai, chatgpt.com and gemini.google.com is captured from the platform's own response stream — real message IDs, the actual model identifier, and true completion events, not screen scraping. Each turn becomes a structured evidence envelope that is canonicalized (RFC 8785), hashed (SHA-256), and timestamped by an RFC 3161 Timestamp Authority with optional Cades sealing. Privacy by architecture: your conversation content never leaves the browser. Only a cryptographic hash is sent for timestamping. Files you attach and files the AI generates are recorded by hash as well. Your evidence log is a chained, tamper-evident ledger stored locally, with hourly integrity anchors. Export it as a self-contained bundle that anyone can verify offline with standard tools — no Sigill account required to check the proofs. Why it matters: when an AI conversation becomes a dispute — what was asked, what was answered, when — logs you can edit prove nothing. Sigill gives each turn an independent, cryptographic timestamp at the moment it happened. Requires a free API key from sigill.ai. Works with Claude, ChatGPT and Gemini.