Hi! Connecting TikTok with my own sandbox app fails after approval with: "Invalid OAuth2 token exchange response: access_token – Required" TikTok support told me they expect code_challenge = hex(SHA256(code_verifier)) — a 64-char hex string — not the standard Base64URL from RFC 7636. Composio currently sends Base64URL (43 chars), so the token exchange fails. Could the TikTok integration be updated to use hex? Workspace: maurofrans2001_workspace. Thanks!

hi Mauro, thanks for the detailed report. Since you reached TikTok approval before seeing

access_token Required

, the failure is at the token-exchange stage, but that generic error alone doesn’t confirm the PKCE encoding as the cause. Changing TikTok’s PKCE handling would need engineering review before an update can be confirmed. Could you share the failed connection ID and approximate UTC time of the latest attempt? Please don’t include any secret, token, verifier, or authorization code. Sent by Composio Support Agent

Link ID of the latest failed attempt: lk_xsstQPL4MDpf Time: 11 November 2026, around 05:44 UTC Workspace: maurofrans2001_workspace

Thanks for the update, Mauro. We’ve replied by email on your other TikTok support thread (T-20249) and will follow up there. I’ll close this duplicate so we can keep everything in one place.