Nixflex - AI Voice Platform for Building AI Phone Agents

Nixflex can send a text automatically once a call has finished - a thank-you, a summary, or a next step. There are two ways to set it up, depending on your structure. For texting during the call, see In-call SMS.

Agent-level template

Set a post_call_sms_template on the agent (with post_call_sms_enabled: true) via the Update agent endpoint. It then fires automatically after every answered call on that agent - both inbound and outbound - on numbers added through the dashboard.

The agent-level template applies only to numbers added through the dashboard. Numbers imported via the API never receive it - one agent often serves many separate businesses, and an agent-level text must never reach another business’s customers. For API-imported numbers, send post-call SMS yourself from the webhook (see below).

curl -X PUT https://api.nixflex.com/v1/agents/agent_125207e452f8714a \
  -H "Authorization: Bearer KEY_ID:KEY_SECRET" \
  -H "Content-Type: application/json" \
  -d '{ "post_call_sms_enabled": true, "post_call_sms_template": "Thanks for speaking with us today, {caller_name}. We will be in touch." }'

Personalise the message with variables, filled in from the call:

Variable	Value	If not available
`{caller_name}`	The caller’s name, if captured during the call	`there`
`{business_name}`	The agent’s name	`our business`
`{call_summary}`	A short summary of the call	empty
`{agent_name}`	The agent’s name	`our team`

If post_call_sms_enabled is true and no template is set, a default is used: Thanks for calling . We appreciate your time.

Write the template so it reads naturally for both inbound and outbound calls if the agent handles both. “Thanks for calling” only fits inbound - prefer neutral wording like “Thanks for speaking with us today”, or use variables to keep it flexible.

Your own, from the webhook

If one agent serves many separate businesses, a single agent-level template would send the same text to every business’s customers. In that case, send the post-call SMS yourself: receive the webhook after each call and send a message tailored to that business from its own number, using the Send SMS API. Each business gets its own wording, branding, and number, with full control over when a message goes out.

When it sends

Post-call SMS sends once, shortly after the call ends, from the business’s own number on whichever carrier that number belongs to. It is skipped when the call reached voicemail, when no template is configured, or when the caller’s number is not available - so messages only go out when they make sense.

In-call SMS - text the caller during the call
Send SMS - send a message via the API, plus length, tracking, compliance and pricing
SMS agent - what happens when the customer texts back
Webhooks - the post-call event you can send your own SMS from

Get started

Guides

Best practices

Core concepts

In-call actions

Features

Bring your own

SMS

Reference

SDKs

Post-call SMS

Agent-level template

Your own, from the webhook

When it sends

​Agent-level template

​Your own, from the webhook

​When it sends

​Related

Agent-level template

Your own, from the webhook

When it sends

Related