Agent skill · magnus919
Send and diagnose transactional email through Twilio SendGrid from a terminal or agent: send messages, check deliverability (bounces and spam reports), and verify Signed Event Webhook signatures (ECDSA P-256) — with a bundled email-cli script that is read-only by default and gates every send behind a --dry-run/--yes confirmation. Use when an agent needs to send a transactional email, triage bounces or spam complaints, or confirm an inbound SendGrid webhook is authentic. Do not use for marketing or bulk email campaigns (that is SendGrid Marketing Campaigns), building email template systems, or other email providers (that is their own tooling).
What it needs
About 5k tokens when loaded.
What this skill does
Transactional Email Operations (SendGrid) Use this skill to send transactional email through Twilio SendGrid and to diagnose delivery: bounces, spam complaints, and the Signed Event Webhook. This is a tool skill for one vendor (SendGrid). Marketing campaigns, template builders, and other providers are out of scope; this skill owns the operational loop for application-triggered email: send it, check it landed, and verify the events claiming so are authentic. Operating contract 1. Read-only discovery before any mutation. Check deliverability signals (bounces, spam reports) freely. The bundled email-cli script makes reads without writing anything. 2. Confirm the target, scope, and rollback path before acting. Sending email puts words in recipients' inboxes in your organization's name: it requires an explicit human directive naming the recipients, sender, and content, plus --dry-run preview and --yes confirmation through email-cli. There is no reliable "un-send" for delivered mail. 3. Respect bounded reads. Suppression listings cap results with --limit; never page past what the task needs. 4. Verify webhooks before trusting them. SendGrid's Signed Event Webhook signs every request; verify the ECDSA signature and timestamp before acting on event data. Unverified webhook endpoints accept forged delivery/bounce events. 5. Keep evidence bounded. Quote short message previews and email addresses; never paste API keys, full message bodies, or suppression lists into chat. 6. Never send to unverified addresses or real users without a directive. Deliverability triage reads are safe; the send path is always gated. The email-cli script scripts/email-cli is an agent-first, stdlib-only CLI over the SendGrid v3 API, including a self-contained ECDSA P-256 signature verifier with no third-party crypto dependency. Exit codes: 0 success, 1 API error or failed verification, 2 usage error. Sends are guarded: without --dry-run or --yes the script refuses with exit 1 and never calls the API. …
How to use it
Reference it in AdaL, Claude Code, Cursor or any coding agent — nothing to install:
@skills magnus919/email