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Overview

Every AI-powered customer interaction has edges — moments where the AI doesn’t have the answer, the customer’s request falls outside configured capability, or the situation requires a human. Fallback flows define what happens at those edges. Without configured fallback flows, edge cases are handled inconsistently. With them, every out-of-scope situation has a defined, controlled response — escalation to an agent, a redirect, a specific message, or a background notification to your team.

How it works

Fallback flows trigger when the AI determines it cannot handle a request within its configured knowledge and actions. When a fallback triggers, Parlel evaluates the configured priority stack and executes the highest-priority applicable flow.

Trigger conditions

  • Knowledge retrieval confidence below threshold
  • Customer request outside the scope of any configured action
  • Journey stage reached without a valid path forward
  • Explicit customer request for human assistance

Response types

Response typeDescription
Connect agentHands the conversation to a human agent via your configured support platform
RedirectSends the customer to a specific URL — a support portal, booking page, or contact form
MessageDelivers a configured message — an acknowledgement, explanation, or instructions

Background actions

In addition to the customer-facing response, fallback flows can trigger background actions that run silently:
Background actionDescription
Send emailNotifies your team that a fallback triggered — with conversation context
WebhookCalls a configured endpoint — for integration with ticketing or CRM systems
ActionExecutes a Parlel action — for example, automatically creating a support ticket

Priority stack

You can configure multiple fallback flows. Parlel evaluates them in priority order and executes the first one that matches the trigger condition. This lets you handle different out-of-scope situations differently.

Relationships

Knowledge Base

Low confidence in knowledge retrieval is a primary fallback trigger. Well-structured knowledge reduces fallback frequency.

Journeys

Journey configuration defines what’s in scope at each stage. Requests outside that scope trigger fallbacks.

Transactions

Every fallback trigger is logged as a transaction — giving visibility into where and why fallbacks fire.

Integrations

Connect agent and webhook fallback types require a configured integration.

Configuration

Creating a fallback flow

Go to Fallback Flows in the portal → New fallback flow. Define:
  • Trigger condition — when this flow activates
  • Priority — where this flow sits in the priority stack
  • Customer response — connect agent, redirect, or message
  • Background actions — optional email, webhook, or action

Monitoring fallbacks

Go to Transactions in the portal and filter by fallback events. High fallback frequency on a specific topic signals that you should add content to your knowledge base or configure a new action.

Reference

ConceptDescription
Fallback flowA configured response to an out-of-scope customer request
Priority stackThe ordered list of fallback flows — first match executes
Connect agentHandoff to a human agent via your support platform
Background actionA silent action triggered alongside the customer response
Reference IDGenerated for every fallback event — format #PRL-XXXXXXXX