Resend Audiences — Manage Email Lists from AI Agents

Quick Use

1. client.audiences.create({name}) to make a list
2. client.contacts.create({audience_id, email, ...}) per signup
3. client.broadcasts.create + send to ship a campaign with auto-unsubscribe

Intro

Resend Audiences is the list-management API — your agent adds recipients on signup, removes them on unsubscribe, segments by tag, and ships compliant unsubscribe links automatically. No separate ESP, no list-import CSV nightmare. Best for: AI agents that nurture leads, newsletter signup flows, onboarding sequences with per-stage list membership, anywhere your agent needs to send to a managed group. Works with: Resend Node + Python SDKs, REST. Setup time: 5 minutes.

Create an audience

from resend import Resend
client = Resend(api_key=os.environ["RESEND_API_KEY"])

audience = client.audiences.create({"name": "TokRepo Weekly Digest"})
print(audience["id"])   # save this — used for all member ops

Add a contact

client.contacts.create({
    "audience_id": audience_id,
    "email": "jane@example.com",
    "first_name": "Jane",
    "last_name": "Smith",
    "unsubscribed": False,
})

Bulk import on signup

async def on_user_signup(user):
    client.contacts.create({
        "audience_id": WEEKLY_DIGEST_ID,
        "email": user.email,
        "first_name": user.first_name,
        "unsubscribed": False,
    })
    # If user opted into multiple lists, repeat per audience_id

Send a broadcast to an audience

broadcast = client.broadcasts.create({
    "audience_id": WEEKLY_DIGEST_ID,
    "from": "TokRepo Weekly <weekly@tokrepo.com>",
    "subject": "5 new AI assets shipped this week",
    "html": render_weekly_digest_html(this_week_assets),
    "scheduled_at": "in 1 hour",   # or "2026-05-12 09:00:00 -0700"
})
client.broadcasts.send(broadcast["id"])

Compliance: unsubscribe + RFC 8058

Resend automatically:

• Adds a one-click unsubscribe link to every broadcast email
• Includes List-Unsubscribe and List-Unsubscribe-Post headers (Gmail/Yahoo 2024 sender requirements)
• Records unsubscribes against the contact — future sends skip them

# Manually unsubscribe (e.g., from a user-facing preference center)
client.contacts.update({
    "audience_id": WEEKLY_DIGEST_ID,
    "email": "jane@example.com",
    "unsubscribed": True,
})

List members

contacts = client.contacts.list({"audience_id": WEEKLY_DIGEST_ID})
for c in contacts["data"]:
    print(c["email"], c["unsubscribed"])

FAQ

Q: Can I do tag-based segmentation? A: Yes — contacts support arbitrary tag fields. Filter at send time by tag value to create dynamic segments. Use a separate audience per major list type, then tags for sub-segmentation.

Q: How does Audiences compare to Klaviyo / Mailchimp? A: Audiences is a primitive — list + send + unsubscribe + compliance. Klaviyo/Mailchimp layer on visual campaign builders, automations, predictive segments. For AI-agent-driven lists where the agent IS the segmentation engine, Audiences is the right size.

Q: What about double opt-in? A: Not built in — Resend assumes you've collected consent before adding. Implement double opt-in by sending a confirm-email through emails.send with a token URL, and only call contacts.create after the recipient clicks confirm.

Source & Thanks

Built by Resend. Audiences API docs at resend.com/docs/api-reference/audiences.

resend/resend-node — official SDK