Zapier

ThunderPhone works with Zapier in two ways. The ThunderPhone app on Zapier connects call events and outbound calling to the other apps your team uses: a finished call can start a Zap, and a Zap can place a call or start a campaign. A Zapier MCP endpoint does a different job. It gives an agent tools to call while it is still talking to someone.

The ThunderPhone app on Zapier

Find it at ThunderPhone on Zapier. When you connect it, you sign in to ThunderPhone through OAuth and approve access for one organization. No API key is copied into Zapier. Connect with an account that has the admin role in that organization; the triggers and actions need it.

Triggers

• Call Completed fires when a phone, web, or test call ends. The event carries the agent, direction, numbers, start and end times, duration, status, end reason, recording URL, and transcript.
• Call Graded fires when a completed call's grade is available, with the score, call outcome, and summary.

Both are instant triggers. Turning a Zap on creates a webhook endpoint in your ThunderPhone organization, and turning it off deletes that endpoint. Every delivery is signed, and the app verifies the signature before the Zap runs.

Actions

• Place Outbound Call starts an outbound call with a saved agent. You pick the agent and the From Number, enter the To Number in E.164 format, and can pass prompt variables as a JSON object.
• Add Contacts to Campaign adds one contact, or a JSON batch of up to 5,000, to a draft campaign. Extra properties on each contact become campaign variables.
• Start Campaign starts or resumes a campaign that has at least one contact.

Search

• Find Call looks up a call by ID and returns it with its transcript and a signed recording URL when one is available.

Before a Zap places calls

Place Outbound Call and Start Campaign dial real phone numbers and start billable calls.

• If ThunderPhone asks your organization to confirm that its outbound calls follow the TCPA and other calling laws, an admin must record that confirmation in the dashboard before a Zap can start calls.
• The From Number must be enabled for outbound calls. Numbers you bring from your own carrier qualify once verified. ThunderPhone-provided numbers start inbound-only, and you can request outbound access for them in the dashboard.
• Place Outbound Call requires an Idempotency Key. Map a stable ID from the trigger or source record, such as the ThunderPhone event ID or a CRM record ID. If Zapier retries the step, ThunderPhone recognizes the key and returns the original call instead of placing a second one. Avoid timestamps, random values, or the Zap ID alone.
• Start Campaign requires Consent to Charge, which confirms the Zap may start billable outbound calls on your account.
• Your organization is responsible for having consent to call each number and for following the calling laws that apply. See outbound calling laws.

Example Zaps

• Call Completed to a CRM. Log an activity for each finished call with its status, end reason, and transcript.
• Call Graded to follow-up. Filter on the call outcome or score and route the call into the right follow-up workflow.
• New lead to a campaign. Add the lead to a draft campaign with Add Contacts to Campaign, then run Start Campaign once someone approves the list.

Call transcripts, summaries and recordings can contain personal or health information. Send them only to apps your organization is allowed to use for that data, under a BAA where health information is involved, and keep only the fields you need.

Set it up

The docs walk through connecting your organization and a first Zap that runs when a call ends: Use ThunderPhone with Zapier.

Zapier tools during a call (MCP)

Use a Zapier MCP endpoint when the agent itself should act mid-conversation, such as submitting a qualified lead before it hangs up. The agent can use exactly the tools your endpoint advertises.

1. Configure the actions you want in your Zapier MCP endpoint. Keep them narrow, with only the fields the call flow needs.
2. In ThunderPhone, open Connections → MCP, add a server, and paste the endpoint URL. The connection uses Streamable HTTP.
3. Save and synchronize the server, then review the discovered tool names. ThunderPhone caches the list, so synchronize again after you change actions at the endpoint.
4. Open the agent in the builder and attach the server in its MCP section. A saved server has no effect on calls until it is attached.
5. In the prompt, say when to use each tool, which details the caller must confirm first, and what to do when a tool returns an error.

The agent decides when to call a tool from the conversation and its prompt. This is function calling over the Model Context Protocol. Have the agent repeat easy-to-mishear values before it calls a tool, and describe the result to the caller only after the tool returns successfully. Lead qualification calls and phone intake forms are common fits.

Which one to use

Use the app when a finished or graded call should start a workflow, or when another app should start calls. Use MCP when the agent needs to act during the call. If your own server should receive call events directly, use ThunderPhone's REST API and webhooks.