skills/sales-sendgrid/SKILL.md
SendGrid platform help — transactional email via Email API (REST + SMTP), Marketing Campaigns (drag-and-drop editor, automations, A/B testing, signup forms, segmentation), Email Validation API, Dynamic Templates (Handlebars), Event Webhooks, Inbound Parse, domain authentication (SPF/DKIM/DMARC), dedicated IPs, suppressions, Design Library, email testing, statistics. Use when SendGrid emails are landing in spam, transactional emails aren't sending, domain authentication is failing, Event Webhooks aren't firing, Dynamic Templates aren't rendering correctly, Marketing Campaigns have low open rates, or SendGrid bounce rates are spiking. Do NOT use for general email marketing strategy (use /sales-email-marketing), cross-platform email deliverability (use /sales-deliverability), or email open/click tracking strategy (use /sales-email-tracking).
npx skillsauth add sales-skills/sales sales-sendgridInstall this skill globally with one command. Works with Claude Code, Cursor, and Windsurf.
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Help the user with SendGrid (Twilio) platform questions — from transactional email via the Email API and SMTP relay through Marketing Campaigns, Dynamic Templates, Event Webhooks, Inbound Parse, domain authentication, dedicated IPs, suppressions, email testing, and integrations.
If references/learnings.md exists, read it first for accumulated knowledge.
Ask the user:
What area of SendGrid do you need help with?
What's your role?
What are you trying to accomplish? (describe your specific goal or question)
If the user's request already provides most of this context, skip directly to the relevant step. Lead with your best-effort answer using reasonable assumptions (stated explicitly), then ask only the most critical 1-2 clarifying questions at the end — don't gate your response behind gathering complete context.
Note: If the user needs a specialized skill, route them there with a brief explanation of why that skill is a better fit.
If the request maps to a specialized skill, route:
/sales-email-marketing/sales-deliverability/sales-email-tracking/sales-integration/sales-funnelOtherwise, answer directly from platform knowledge using the reference below.
Read references/platform-guide.md for detailed module documentation, pricing, integrations, and data model.
You no longer need the platform guide details — focus on the user's specific situation.
Based on the user's specific question:
Sending transactional email via the API:
npm install @sendgrid/mail for Node.js)sgMail.setApiKey(process.env.SENDGRID_API_KEY)to, from, subject, text/html (or templateId + dynamicTemplateData)Setting up Marketing Campaigns automation:
Configuring domain authentication:
v=DMARC1; p=quarantine; rua=mailto:[email protected])Setting up Event Webhooks:
event, email, timestamp, and custom argsSetting up Inbound Parse:
mx.sendgrid.netBest-effort from research — verify details against current SendGrid documentation.
sg_event_id changes on retries — do NOT use it for deduplication. Despite the docs saying sg_event_id is "a unique ID to this event that you can use for deduplication purposes," the ID changes on every retry attempt. Same email, same event, same timestamp — but a different sg_event_id. Build a composite dedup key instead: ${sg_message_id}:${event}:${email}. Store processed keys in Redis (with 48-hour TTL to cover SendGrid's 24-hour retry window) or a database, and check before processing each event.sgMail.send() calls concurrently, you'll hit EMFILE errors (file descriptor limit). The SDK creates a new connection per request. Use sequential sending (for...of with await), a concurrency limiter (p-limit set to 2-10), or personalizations (up to 1000 recipients per single request) to reduce connection count.sgMail.send(), SendGrid queues them server-side. For time-sensitive sends, use personalizations (same content, different recipients in one request) or send individual calls with concurrency control rather than one massive batch.references/learnings.md with today's date./sales-email-marketing — Email marketing strategy and best practices (platform-agnostic)/sales-deliverability — Cross-platform email deliverability — SPF/DKIM/DMARC, warmup, inbox placement/sales-email-tracking — Email open and click tracking strategy/sales-integration — Connect SendGrid to other tools via Zapier, Make, or API/sales-funnel — Funnel strategy and conversion optimization/sales-do — Not sure which skill to use? The router matches any sales objective to the right skill. Install: npx skills add sales-skills/sales --skill sales-doUser says: "I need to send password reset and welcome emails from my Node.js app using SendGrid." Skill does:
@sendgrid/mail and configure the API key via environment variable{{reset_link}}) and one for welcome (with {{first_name}}, {{login_url}})sgMail.send() with templateId and dynamicTemplateDataUser says: "We're moving our newsletter from Mailchimp to SendGrid Marketing Campaigns. What's the process?" Skill does:
User says: "I want to track which emails bounce and get delivered so I can update our CRM." Skill does:
sg_message_id as a deduplication keySymptom: Deliverability drops and emails start landing in spam shortly after upgrading to a Pro or Advanced plan with a dedicated IP
Cause: The dedicated IP is new and has no sending reputation. Mailbox providers (Gmail, Yahoo, Outlook) are cautious about unknown IPs and will throttle or spam-folder email from them.
Solution: Enable automated IP warmup in Settings > IP Addresses (it should be on by default for new IPs). If you turned it off, re-enable it. During warmup, SendGrid splits your traffic between the new dedicated IP and the shared IP pool, gradually shifting volume to the dedicated IP over weeks. Do not send your full volume on a cold IP. If deliverability is already damaged, pause high-volume sends, re-enable warmup, and start with your most engaged recipients. Monitor mailbox-provider stats to see which providers are rejecting. See /sales-deliverability for a comprehensive warmup guide.
Symptom: You configured an Event Webhook URL but your endpoint is not receiving any event data Cause: The webhook URL is not publicly accessible, HTTPS certificate is invalid, the endpoint is returning non-2xx status codes, or the webhook is not enabled. Solution: Verify the webhook is enabled in Settings > Mail Settings > Event Webhook. Ensure your URL is publicly reachable (not localhost or behind a firewall). Check that your HTTPS certificate is valid and not self-signed. Test the endpoint manually with a POST of sample JSON. Check that your endpoint returns 2xx status codes within 3 seconds — SendGrid treats timeouts and errors as failures and will retry, but eventually stops after 24 hours. Use a tool like ngrok for local development testing. Check SendGrid's Event Webhook activity log for delivery attempts and error codes.
Symptom: Emails deferred or rejected with 421 4.7.32 From: header isn't aligned with either the authenticated SPF or DKIM organizational domain — especially common with scheduled emails
Cause: The From address domain doesn't match the domain you authenticated in SendGrid. For example, sending from a gmail.com address through SendGrid, or sending from [email protected] when only notifications.example.com is authenticated. Gmail and Yahoo enforce DMARC alignment strictly since Feb 2024.
Solution: Go to Settings > Sender Authentication > Authenticate Your Domain and authenticate the exact domain you send from. Add the CNAME records SendGrid generates to your DNS. Make sure your From address matches — if you authenticated example.com, send from [email protected]. Add a DMARC record to your DNS: v=DMARC1; p=none; rua=mailto:[email protected] (start with p=none to monitor). If you're on a shared IP plan and still seeing throttling after fixing authentication, the shared IP may have poor reputation — check it at mxtoolbox.com and consider a dedicated IP (Pro plan).
Symptom: Duplicate webhook events processed despite checking sg_event_id — same email, same event type, same timestamp, but different sg_event_id values
Cause: sg_event_id changes on every retry attempt. Despite the docs calling it a deduplication key, it is unique per delivery attempt, not per logical event.
Solution: Build a composite dedup key from fields that ARE stable across retries: ${sg_message_id}:${event}:${email}. Store processed keys in Redis with a 48-hour TTL (covers SendGrid's 24-hour retry window with margin) or a database table with a unique constraint. Check before processing each event. For high-volume systems, use a Bloom filter or Redis SET with EXPIRE for fast lookups.
Symptom: Error: connect EMFILE when sending hundreds or thousands of emails — typically the first few batches succeed and then later ones fail
Cause: Each sgMail.send() call opens a new HTTP connection. Node.js has a default file descriptor limit (~1024). Concurrent requests exhaust available sockets before earlier connections close. The SendGrid Node SDK does not pool connections.
Solution: Three approaches (pick one): (1) Send sequentially: for (const msg of messages) { await sgMail.send(msg); } — slowest but simplest. (2) Limit concurrency: use p-limit set to 2-10 concurrent requests: const limit = pLimit(5); await Promise.all(msgs.map(m => limit(() => sgMail.send(m))));. (3) Use personalizations: if recipients get the same content with different substitution data, send up to 1000 recipients in a single API call using the personalizations array — this is the most efficient approach and uses just one HTTP connection.
Symptom: Contacts were imported or added via the API but do not appear in segments or lists as expected
Cause: Contact ingestion in Marketing Campaigns is asynchronous — it can take minutes to hours for contacts to be fully indexed and available in segments. Alternatively, the import may have partially failed due to invalid fields or duplicate handling.
Solution: Check the import status in Marketing > Contacts > Imports for errors or warnings. Allow up to 2 hours for large imports to fully index. Verify that custom field names in the import match the custom fields defined in your SendGrid account (mismatches cause fields to be silently dropped). Check that contacts have the expected field values by searching for a specific contact in the UI. For API-added contacts (PUT /v3/marketing/contacts), check the response for the job_id and poll GET /v3/marketing/contacts/imports/{id} for status. If contacts appear in the list but not the segment, review the segment query conditions — ensure the field names and operators match the actual contact data.
tools
Waitlister platform help — pre-launch waitlist platform with hosted landing pages, points-based viral referrals, built-in email broadcasts, REST API, and five HMAC-signed webhook events. Use when choosing Free (100 subscribers) vs Launch $15/mo (unlimited subs, referrals + broadcasts) vs Growth $49/mo (API, webhooks, Klaviyo/Mailchimp/Kit sync, fraud detection unlock here) vs Business $129/mo, building a webhook handler that verifies X-Webhook-Signature, webhooks auto-disabled after 10 consecutive failures, API signups bypassing referral fraud detection because client_ip/fingerprint weren't forwarded, granting bonus points or pulling top referrers via the API for reward fulfillment, broadcast send caps forcing an ESP handoff, automating without Zapier (Waitlister has none — webhooks/API only), or comparing Waitlister vs LaunchList/KickoffLabs/GetWaitlist/Prefinery. Do NOT use for list-growth strategy (use /sales-audience-growth) or LaunchList help (use /sales-launchlist).
development
LaunchList platform help — viral pre-launch waitlist platform with one-time lifetime pricing, gamified referrals (queue jumping, leaderboard, position inflation), embed widget + custom form POST endpoint, new_user/email_verify webhooks, Zapier, and spam protection. Use when choosing Free (100 submissions) vs Launch $29 (500) vs Grow $79 one-time (10K — webhooks, Zapier, team unlock here), wiring waitlist signups into Mailchimp/Kit/HubSpot or a CRM because LaunchList has no email broadcast system, needing programmatic access when there is no public REST API yet (form POST + webhook workaround), building a webhook handler with referred_by referral attribution, blocking disposable-email or bot signups on a viral waitlist, a custom signup form not submitting or not tracking referrals, or comparing LaunchList vs KickoffLabs/Viral Loops/Prefinery/GetWaitlist on one-time vs subscription pricing. Do NOT use for list-growth strategy (use /sales-audience-growth) or KickoffLabs help (use /sales-kickofflabs).
development
UpViral platform help — viral referral marketing and list-building platform (by Emarky) for viral sweepstakes, giveaway/reward campaigns, pre-launch waiting lists, and milestone referrals, with REST API (`app.upviral.com/api/v1/`, form-encoded `uvapikey` + `uvmethod`), Callback-URL webhooks, IP-based fraud detection, and 30+ ESP/CRM integrations. Use when campaigns aren't tracking referral points, deciding between Starter $79/mo (10K leads, NO API) vs Business $119/mo (API + webhooks) vs Premium $319/mo, the API erroring because you're on Starter where API/webhooks are gated, building a pipeline with `add_contact`/`get_leads`/`get_leads_points`, interpreting same-IP suspicious-referral flags, or picking UpViral over Viral Loops/Vyper/Gleam. Do NOT use for newsletter audience growth (use /sales-audience-growth), KickoffLabs help (use /sales-kickofflabs), merge-tag referrals (use /sales-referralkit), SparkLoop recommendations (use /sales-sparkloop), or multi-level Level 1/2/3 tracking (use /sales-referralhero).
tools
ReferralHero platform help — full-stack referral, affiliate, waitlist, contest, and NPS platform with REST API, webhooks, Zapier, native ESP connectors, multi-level referral tracking (Level 1/2/3), coupon groups, anti-fraud, and a 5,000 calls/hour limit. Use when referrals aren't tracking, deciding between Free (no API) vs PRO $199/mo (API + webhooks) vs PREMIUM $399/mo (ReCaptcha + SMS Verification), auth failing with `no_token` or `Bearer` vs `X-API-Key`, Level 2/3 counts off from calling `level_2_all_referrals` not `level_2_referrals`, bulk 429s from not chunking the 500-transaction `add_bulk_transactions` limit, coupon endpoints 404 without a coupon group, reward fulfillment (`promote` then `unlock_promoted_reward`) failing, or comparing to SparkLoop/ReferralKit/GrowSurf. Do NOT use for newsletter audience growth (use /sales-audience-growth), merge-tag referrals (use /sales-referralkit), SparkLoop recommendations (use /sales-sparkloop), or affiliate strategy across tools (use /sales-affiliate-program).