Reply to a conversation

Sends a reply in an existing conversation (DM, comment, or mention) on Instagram, Facebook, LinkedIn, TikTok (comments only), YouTube (comments only), X (DM-only), or Threads (replies and mentions; needs a Threads connection with the reply permission, else 401 reauth_required). You can only reply to conversations that already exist in your inbox — the API cannot start new conversations (Instagram requires the user to message first, and cold outreach violates Meta policy). Direct-message replies must be within the platform's messaging window (24 hours since the user's last message); replies outside the window are rejected. TikTok replies are text-only, capped at 150 characters (400 validation_error beyond that), and can take a few minutes to appear on TikTok while they pass spam review. Each workspace can send up to 1,000 replies per rolling 24 hours (429 reply_limit_reached beyond that) — contact robert@omnisocials.com if you need a higher limit. X DM replies debit 2 credits from the company balance before the send (auto-refunded if the send fails) and can return 402 insufficient_credits or 402 x_inbox_suspended. Requires the inbox:write scope (API keys) or the access_social_inbox permission (OAuth/MCP).