Synthflow voice quality. WFW integration depth. No tradeoff.
WFW's ToolGateway translates Synthflow tool events to the WFW canonical schema — your CRM, PMS, and scheduling systems receive the same clean WFW events they always have.
Prefer Synthflow's voice output? Use it. Switching to Synthflow doesn't require rebuilding a single downstream integration.
ToolGateway Translation — Synthflow Tool Event
Engine-agnostic architecture
Synthflow, Vapi, Retell, and ElevenLabs all supported. WFW normalizes all of them to the same integration layer.
Capabilities
What this integration enables.
Three concrete capabilities unlocked by connecting Synthflow to WFW.
ToolGateway
Synthflow Tool Events → WFW ToolGateway
When a Synthflow agent fires a tool event via its REST API, WFW's ToolGateway receives the call and translates the Synthflow-specific payload into the WFW ToolEvent schema before routing to downstream integrations.
ToolGateway
REST API Normalization Layer
Synthflow's REST API structure differs from Vapi and Retell's webhook patterns. WFW handles the protocol differences internally — your CRM and PMS integrations receive the same normalized WFW event regardless of which engine sent the signal.
ToolGateway
Cross-Engine Call History Continuity
Every call record lives in WFW, not in Synthflow. When you migrate to Synthflow from another engine, your historical call data, extraction records, and agent performance analytics remain in WFW — accessible through the same API endpoints.
Data Flow
How it works.
What moves between WFW and Synthflow — from agent provisioning to extraction delivery.
WFW configures Synthflow agent context
Before a call, WFW assembles the agent's context — system prompt, tool definitions, integration credentials — and provisions the Synthflow agent via Synthflow's REST API. The agent knows how to call WFW's ToolGateway when a lookup or action is needed.
Synthflow handles voice processing
Synthflow manages real-time STT, LLM processing, and TTS delivery. When the agent's response requires a data lookup (patient record, reservation, service history), it fires a tool event to WFW's ToolGateway endpoint.
ToolGateway translates Synthflow's schema
WFW maps Synthflow's tool event format — field names, action types, response structure — to the WFW ToolEvent canonical schema. Downstream systems (Dentrix, Salesforce, OpenTable) receive a clean WFW event.
Unified extractions across all engines
GET /v2/calls/{id}/extractions returns structured data in WFW's schema — not Synthflow's. Your reporting pipeline, follow-up automation, and CRM sync logic work identically for Synthflow calls as for any other engine.
Use Cases
Before and after.
Real scenarios where WFW's abstraction layer makes engine choice a preference, not a commitment.
Before
Switching voice engines means auditing every tool definition, rewriting webhook handlers for the new provider's payload format, and retesting all downstream integrations from scratch.
After
Point WFW at Synthflow in agent settings. ToolGateway handles the translation. Every integration — CRM, scheduling, dental PMS — works immediately without changes.
Before
Testing Synthflow's voice quality against another engine requires building and maintaining two parallel integration stacks with separate reporting.
After
WFW routes a traffic split between engines. All calls normalize to WFW schema. Compare quality, latency, and conversion rate from a single WFW analytics view.
Before
Certain regulated clients or data residency requirements mandate specific voice vendors. Meeting each client's requirement means re-engineering the agent stack per client.
After
Configure Synthflow as the voice engine for clients with specific vendor requirements. WFW integration layer, compliance guardrails, and extraction rules stay constant.
Technical Details
Integration specifications.
REST API protocol, normalization approach, and data handling for your engineering team.
| Tool event ingestion | Synthflow tool event → WFW ToolGateway REST endpoint → normalized WFW ToolEvent |
| Protocol | REST API — WFW handles differences between Synthflow's API structure and other engine protocols |
| Auth method | Synthflow API key stored encrypted in WFW vault |
| Normalization scope | Field mapping, action type translation, response format — fully handled by ToolGateway |
| Call record storage | All calls stored in WFW. Synthflow call/session ID stored as external_ref for cross-reference. |
| Switching cost | Zero downstream changes required when switching to or from Synthflow. |
API Endpoints
The WFW endpoints enabled by Synthflow.
Identical /v2/ endpoints across all supported engines. Your API client code doesn't change when you switch to or from Synthflow.
Full API Reference →Available Endpoints
/v2/calls/initiateTrigger outbound call — WFW provisions Synthflow agent and initiates
/v2/calls/{id}/extractionsRetrieve normalized extraction data from a Synthflow-handled call
/v2/agents/{id}Check agent config — confirms Synthflow as active voice engine
Setup
Connect Synthflow in three steps.
Add the credential, select the engine, verify the ToolGateway. Done.
Add Synthflow API key
Enter your Synthflow API key in WFW admin under Integrations → Voice Engines → Synthflow. Encrypted and stored in the WFW vault.
Set Synthflow as active engine
In your agent's settings, select Synthflow as the voice engine. WFW provisions Synthflow agents using your stored credentials.
Verify ToolGateway endpoint
WFW registers its ToolGateway REST endpoint as the tool handler in your Synthflow agent configuration. Confirm tool events are routing correctly.
Get Started
Connect Synthflow to your voice agents.
Your preferred voice engine. WFW's full integration depth behind it. Switch anytime without breaking downstream systems.
Connect SynthflowQuestions? Talk to our team →