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Callerapi for AI agents

CallerAPI provides branded caller ID lookups, helping a business show its name on outgoing calls and screen incoming numbers for spam or fraud risk. 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 CallerapiSee the 7 actions ↓
CommunicationAPI keyMCP + RESTcallerapi.com
AUDIT LOG · CALLERAPIPOLICY: acme-support
09:41:07 · claude · u_8f2read
callerapi.list_webhook_subscriptions
List Webhook Subscriptions✓ allowed · 212ms
09:41:08 · claude · u_8f2read
callerapi.test_webhook
Test Webhook✓ allowed · 164ms
09:41:09 · claude · u_8f2write
callerapi.subscribe_daily_reports
Subscribe to Daily Spam Reports✓ approved · approved by user
09:41:12 · claude · u_8f2destructive
callerapi.unsubscribe_daily_reports
Unsubscribe from Daily Reports✕ blocked · policy: deny
EVERY CALLERAPI CALL, ON THE RECORD
01 · USE CASES

What agents do in Callerapi.

01

Look up an incoming number

Look up a phone number's details before deciding whether to trust or block an incoming call.

02

Check spam report subscriptions

List the webhook subscriptions for spam reports to confirm alerts are still wired up.

03

Subscribe to daily spam reports

Subscribe an account to daily spam reports so flagged numbers surface automatically.

02 · ACTIONS

7 Callerapi actions, graded by risk.

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

read

4

Look things up. Allowed by default.

  • callerapi.get_user_information
    Get User Information
  • callerapi.list_webhook_subscriptions
    List Webhook Subscriptions
  • callerapi.get_phone_number_information
    Get Phone Number Information
  • callerapi.test_webhook
    Test Webhook

write

2

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

  • callerapi.subscribe_daily_reports
    Subscribe to Daily Spam Reports
  • callerapi.dispatch_reports_manually
    Dispatch Reports Manually

destructive

1

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

  • callerapi.unsubscribe_daily_reports
    Unsubscribe from Daily Reports
03 · HOW IT WORKS

Callerapi in three steps.

  1. 01Your users connect CallerapiThey add their Callerapi api key on Arc0 Connect, under your brand. It goes straight into the vault.
  2. 02You set the rulesReads run, writes like “subscribe to Daily Spam Reports” can wait for the user, and “unsubscribe from Daily Reports” can be denied outright.
  3. 03Any agent can actYour agent calls Callerapi 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('callerapi', {
  read: 'allow',
  write: 'ask',        // subscribe_daily_reports
  destructive: 'deny',  // unsubscribe_daily_reports
})

# 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 Callerapi connects.

Users add their Callerapi 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 Callerapi 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 Callerapi from any agent.

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

More communication apps.

Slack168 actionsMicrosoft Teams174 actionsDiscord28 actionsSlackbot101 actions2chat5 actionsAimTell15 actionsAndroid Texter11 actionsDialpad192 actions
ALL COMMUNICATION APPS →
07 · FAQ

Callerapi and Arc0, answered.

Q01

Can I use Callerapi with Claude, ChatGPT or Cursor?

Yes. Connect Callerapi 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 Callerapi actions you allow.

Q02

How do users connect Callerapi?

Users add their Callerapi 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 Callerapi actions can my agent take?

7 in total: 4 read, 2 write and 1 destructive, such as “subscribe to Daily Spam Reports”. Your policies decide which of them each agent may call.

Q04

Can I stop my agent from deleting things in Callerapi?

Yes. Actions like “unsubscribe from Daily Reports” 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 Callerapi too?

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

Get started

Plug Callerapi into your agent.

Your users connect Callerapi once, under your brand. Your agent gets 7 actions behind your policies, with every call on the record.

Connect CallerapiBrowse all apps →

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