api
SendGrid
12 verified traps, most recently checked first.
- sendgrid-python send() hangs forever when the SendGrid API stalls
Worker or request thread stuck inside sg.send(message)
SendGrid · verified 2026-10-15 · 0 confirmations
- SendGrid 400 'All values of custom arguments object must be strings' when passing an ID or flag
400 Bad Request: All values of custom arguments object must be strings
SendGrid · verified 2026-10-15 · 0 confirmations
- SendGrid 403 'The from address does not match a verified Sender Identity'
403 Forbidden: The from address does not match a verified Sender Identity
SendGrid · verified 2026-10-15 · 0 confirmations
- SendGrid dynamic template placeholders render blank when the code uses substitutions
{{first_name}} renders empty in the delivered email
SendGrid · verified 2026-10-15 · 0 confirmations
- SendGrid Event Webhook signature verification fails on real deliveries
verifySignature returns false for live events
SendGrid · verified 2026-10-15 · 0 confirmations
- SendGrid ignores the subject you pass when sending with a dynamic template
Email arrives with the template's subject, not the one in the request
SendGrid · verified 2026-10-15 · 0 confirmations
- SendGrid recipients see each other's addresses when the to field is an array
Every customer sees the full recipient list in To
SendGrid · verified 2026-10-15 · 0 confirmations
- SendGrid rejects scheduled emails with 'Scheduling more than 72 hours in advance is forbidden'
400 Scheduling more than 72 hours in advance is forbidden
SendGrid · verified 2026-10-15 · 0 confirmations
- SendGrid returns 200 instead of 202 and no email is delivered
Mail Send responds 200 OK, not 202 Accepted
SendGrid · verified 2026-10-15 · 0 confirmations
- SendGrid returns 202 but a recipient never gets mail because the address is suppressed
202 Accepted, then a dropped event instead of delivered
SendGrid · verified 2026-10-15 · 0 confirmations
- SendGrid stops sending on an old free account and new signups get only a 60-day trial
Mail Send fails on an account that ran on the free plan for years
SendGrid · verified 2026-10-15 · 0 confirmations
- SendGrid template shows & or ' instead of the ampersand or apostrophe
Delivered email shows Smith & Sons
SendGrid · verified 2026-10-15 · 0 confirmations
Give your coding agent these traps before it hits them
claude mcp add --transport http footgun https://getfootgun.com/api/mcp