Handle Retell's Inbound call webhooks
Configured with Google Sheets, Respond To Webhook, Webhook. Review the connections and setup before adapting this template.
Node categories in this workflow
- Trigger
- Web / API
- Data store
Icons describe general node roles, inferred from node types. Inspect the parameters for the configured action.
Drag to pan; use + and − to zoom. Reconstructed from the exported node positions; nothing runs here. Dashed lines represent non-main connections. Full node names and notes appear below.
How it works
The exported workflow contains the following configured nodes. Their connections are shown above; inspect the JSON for the complete logic, expressions, and external actions.
| Node | Category | Type | Operation |
|---|---|---|---|
| Webhook | Trigger | Webhook | See node parameters |
| Respond to Webhook | Web / API | Respond To Webhook | See node parameters |
| Get user in DB by Phone Number | Data store | Google Sheets | See node parameters |
Setup
- Download the JSON and import it into an isolated n8n instance. Leave the workflow inactive.
- Connect your own credentials through n8n’s credential store. Replace
REPLACE_WITH_*values with your resource identifiers. - Inspect API destinations, Code nodes, database queries, file paths, and outbound actions.
- Run with synthetic data and harmless destinations. Enable triggers only after checking the actual outputs.
Requirements
An n8n instance with the listed node types and compatible versions. Service-connected workflows may require accounts, credentials, or paid APIs.
Credential types declared in the source
googleSheetsOAuth2Api
Workflow notes
Handle Retell's Inbound call webhooks
Handle Retell's Inbound call webhooks
Overview
- This workflow provides Retell agent builders with a simple way to populate dynamic variables using n8n.
- The workflow fetches user information from a Google Sheet based on the phone number and sends it back to Retell.
- It is based on Retell's Inbound Webhook Call.
- Retell is a service that lets you create Voice Agents that handle voice calls simply, based on a prompt or using a conversational flow builder.
Prerequisites
- Have a Retell AI Account
- Create a Retell agent
- Purchase a phone number and associate it with your agent
- Create a Google Sheets - for example, make a copy of this one.
- Your Google Sheet must have at least one column with the phone number. The remaining columns will be used to populate your Retell agent’s dynamic variables.
- All fields are returned as strings to Retell (variables are replaced as text)
How it works
- The webhook call is received from Retell. We filter the call using their whitelisted IP address.
- It extracts data from the webhook call and uses it to retrieve the user from Google Sheets.
- It formats the data in the response to match Retell's expected format.
- Retell uses this data to replace dynamic variables in the prompts.
How to use it
See the description for screenshots!
- Set the webhook name (keep it as POST).
- Copy the Webhook URL (e.g., `https://example.invalid/REPLACE_WITH_N8N_ENDPOINT and paste it into Retell's interface. Navigate to "Phone Numbers", click on the phone number, and enable "Add an inbound webhook".
- In your prompt (e.g., "welcome message"), use the variable with this syntax:
{{variable_name}}(see Retell's documentation). - These variables will be dynamically replaced by the data in your Google Sheet.
Notes
- In Google Sheets, the phone number must start with
'+'. - Phone numbers must be formatted like the example: with the
+, extension, and no spaces. - You can use any database—just replace Google Sheets with your own, making sure to keep the phone number formatting consistent.
Sticky Note3
Change the path if needed
Sticky Note
Replace with your own Google Sheets, including the dynamic variables of your Retell Agent
Sticky Note2
Adapt the response to match your Retell dynamic variables
Handle Retell's Inbound call webhooks
Handle Retell's Inbound call webhooks
Purpose and structure
This folder contains the Handle Retell's Inbound call webhooks workflow. Its executable nodes use googleSheets, respondToWebhook, webhook. The table and connection map below are derived from the JSON, not an inferred guarantee of behavior.
Setup
Import inactive. Configure your own credentials and replace REPLACE_WITH_* values. Review external destinations and Code nodes before running.
Entry points
Webhook
Verification
Sanitized source candidate; not runtime-tested. This overview is generated from node metadata. Read the folder README for the connection map, credential types, and license.
Attribution
https://github.com/Zie619/n8n-workflows/blob/94007c1445d9258a7da116646b79473e7c7c3282/workflows/Googlesheets/0818_GoogleSheets_Respondtowebhook_Import_Webhook.json MIT; preserve source notices.