POPCORN Witness Verifier for ChatGPT

io.github.violetclaire/popcorn-tain-verifier

MCP server for verifying receipts: POPCORN-WITNESS/2.0 signature, digest, and time. Free, read only.

client:ChatGPT transport:streamable-http tools:1

Install POPCORN Witness Verifier in ChatGPT

Settings → Connectors → Advanced → Developer mode

https://popcorn-tain-verify-mcp-v2.violetherod.workers.dev/mcp

Custom connectors are a paid-plan feature and take a remote URL only. ChatGPT cannot run a packaged server locally. ChatGPT docs