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Loops.so for AI agents

Loops.so is an email platform for SaaS companies to send product, marketing, and transactional emails triggered by user events inside their product. Connect it once through Arc0, and your agent, or Claude, ChatGPT and Cursor, can use it through one MCP endpoint, limited to what each user approved.

Connect Loops.soSee the 12 actions ↓
EmailAPI keyMCP + RESTloops.so
AUDIT LOG · LOOPS.SOPOLICY: acme-support
09:41:07 · claude · u_8f2read
loops_so.list_custom_fields
List Custom Fields✓ allowed · 212ms
09:41:08 · claude · u_8f2read
loops_so.find_contact
Find Contact✓ allowed · 164ms
09:41:09 · claude · u_8f2write
loops_so.create_contact
Create Contact✓ approved · approved by user
09:41:12 · claude · u_8f2destructive
loops_so.delete_contact
Delete Contact✕ blocked · policy: deny
EVERY LOOPS.SO CALL, ON THE RECORD
01 · USE CASES

What agents do in Loops.so.

01

Create a contact from a signup

Create a new contact when a user signs up so they enter onboarding email flows.

02

Send a triggered event

Send an event, such as a completed purchase, to trigger the right transactional email.

03

Approve before deleting a contact

Require approval before deleting a contact, since it removes their email history and preferences.

02 · ACTIONS

12 Loops.so actions, graded by risk.

Every Loops.so action is tagged read, write or destructive, so one policy covers the whole app and new actions inherit the right default.

read

7

Look things up. Allowed by default.

  • loops_so.find_contact
    Find Contact
  • loops_so.get_mailing_lists
    Get Mailing Lists
  • loops_so.list_custom_fields
    List Custom Fields
  • loops_so.get_contact_properties
    Get Contact Properties
  • loops_so.get_dedicated_sending_ips
    Get Dedicated Sending IPs
  • loops_so.list_transactional_emails
    List Transactional Emails
  • loops_so.test_api_key
    Test API Key

write

4

Create and change things. Allow, or ask the user first.

  • loops_so.send_event
    Send Event
  • loops_so.create_contact
    Create Contact
  • loops_so.update_contact
    Update Contact
  • loops_so.create_contact_property
    Create Contact Property

destructive

1

Delete, cancel or archive. Ask first, or deny outright.

  • loops_so.delete_contact
    Delete Contact
03 · HOW IT WORKS

Loops.so in three steps.

  1. 01Your users connect Loops.soThey add their Loops.so api key on Arc0 Connect, under your brand. It goes straight into the vault.
  2. 02You set the rulesReads run, writes like “create Contact” can wait for the user, and “delete Contact” can be denied outright.
  3. 03Any agent can actYour agent calls Loops.so through the Arc0 SDK or MCP, and so can Claude, ChatGPT and Cursor. Every call lands on the audit log.
POLICY.TS
await arc0.policies.set('loops_so', {
  read: 'allow',
  write: 'ask',        // create_contact
  destructive: 'deny',  // delete_contact
})

# Claude Code: the same connection, one URL
$ claude mcp add --transport http arc0 \
    https://mcp.arc0.ai/u/u_8f2
04 · AUTH AND DATA

How Loops.so connects.

Users add their Loops.so api key on Arc0 Connect. It is encrypted in the vault, never shown to the model, and each user can rotate or revoke it at any time.

The same Loops.so connection serves your agent over MCP and your own backend over REST and the proxy, so a user connects once. How Arc0 handles credentials →

AUTH
API key
CREDENTIALS
Per-tenant encrypted vault
MODEL SEES
Results only, never credentials
AUDIT LOG
Every call, on every plan
05 · WORKS WITH

Use Loops.so from any agent.

Claude
ChatGPT
Cursor
Codex
VS Code
OpenAI Agents SDK
Claude Agent SDK
Vercel AI SDK
Mastra
LangGraph
06 · RELATED

More email apps.

Gmail62 actionsOutlook306 actionsSendGrid364 actionsMixmax94 actionsElastic Email91 actionsResend66 actionsLettr60 actionsPostmark46 actions
ALL EMAIL APPS →
07 · FAQ

Loops.so and Arc0, answered.

Q01

Can I use Loops.so with Claude, ChatGPT or Cursor?

Yes. Connect Loops.so to Arc0 once, then add your Arc0 MCP URL to Claude, ChatGPT, Cursor, Claude Code or any other remote-MCP client. Each assistant only gets the Loops.so actions you allow.

Q02

How do users connect Loops.so?

Users add their Loops.so api key on Arc0 Connect. It is encrypted in the vault, never shown to the model, and each user can rotate or revoke it at any time.

Q03

Which Loops.so actions can my agent take?

12 in total: 7 read, 4 write and 1 destructive, such as “create Contact”. Your policies decide which of them each agent may call.

Q04

Can I stop my agent from deleting things in Loops.so?

Yes. Actions like “delete Contact” are graded destructive. Set destructive actions to deny, or to ask so the user approves each one, and blocked calls still show up on the audit log.

Q05

Can my own backend call Loops.so too?

Yes. The same Loops.so connection is available over REST and through the Arc0 proxy, so your product and your agent share one connection per user.

Get started

Plug Loops.so into your agent.

Your users connect Loops.so once, under your brand. Your agent gets 12 actions behind your policies, with every call on the record.

Connect Loops.soBrowse all apps →

Free to build · MCP + REST · Audit log on every plan