All writes require contract negotiation with eClinicalWorks. Cobalt has existing write access.

No native webhooks. Cobalt provides real-time data feeds.

Per-practice activation and build version management is complex. Cobalt handles multi-practice provisioning.

eClinicalWorks offers solid FHIR R4 read coverage and reasonable write capabilities, but every write operation requires a separate contract. There are no webhooks or event-driven integration options.

eClinicalWorks

eCW FHIR Developer Portal

eCW FHIR Documentation

healow Developer Portal

healow FHIR Documentation

Interoperability Overview

ONC Certification Page

EHI Export Documentation

Zus Health — eCW Integration

Iguana — eCW Integration Guide

FHIR R4. Read access is self-service; all writes are contract-gated. No webhooks.

Notes write-back involves multiple patterns (SMART launch, document upload) with potential scope approval. Cobalt provides a unified write interface.

Push-based event subscriptions are alpha-only and scopes aren't self-service. Cobalt provides production-ready eventing.

Quarterly breaking changes require continuous maintenance. Cobalt uses RPA-based integration, bypassing API version management entirely.

athenahealth has a large proprietary API surface covering clinical, scheduling, and billing workflows. Multiple write-back patterns are described in vendor materials (e.g., athenaOne APIs, SMART launch, document upload), depending on endpoint and access tier. The push-based event system is still in alpha.

athenahealth

Main API Docs

Developer Console

All APIs Reference

FHIR APIs

athenaOne Core IG v5.8.0

Onboarding Guide

Authorization Overview

Changed Data Subscriptions

FHIR Event Subscriptions

ONC Certification

Marketplace Partners

Developer Portal Overview

Large proprietary REST API surface + FHIR R4. Multiple write-back patterns supported. Self-service sandbox available for development.

No write API exists for clinical data. Cobalt provides write access through alternative integration pathways.

No scheduling API exists. Cobalt enables appointment workflows for Practice Fusion.

No webhooks or event-driven integration. Cobalt provides real-time data access.

Unclear onboarding path with no developer portal. Cobalt has an established integration with Practice Fusion.

Practice Fusion is effectively read-only for third-party integrators. There is no write API for clinical data, no scheduling API, no webhooks, and the developer onboarding path is unclear.

Practice Fusion

FHIR API Specifications

PDS API Developer Guide

Labs Documentation

ONC Certified EHR

PDS Registration Portal

Veradigm FHIR Endpoint Directory

Read-only FHIR R4. No write API, no scheduling, no webhooks. High integration barrier.

No webhooks available. Cobalt provides real-time event-driven data from ModMed.

Dual API track with different auth methods is complex. Cobalt provides a single unified interface.

Per-practice credential management creates operational overhead. Cobalt handles credential lifecycle.

ModMed provides strong write access through its proprietary FHIR API after a partner onboarding process. The dual-track API architecture (proprietary vs. certified) means maintaining two integration paths with different auth methods.

ModMed

API Portal

Proprietary API Documentation (PDF)

Certified FHIR API Documentation (PDF)

ONC Certification Press Release

Become a Partner

Certified API Vendor Registration

FHIR Endpoint Directory

synapSYS Marketplace

Dual-track FHIR R4 APIs (proprietary + certified) with write access via partner onboarding.

Automatically generate clinical notes from patient encounters using AI.

AI Medical Scribe

Real-time encounter capture

Post-visit summarization

Ambient listening with push-back

Digitize patient intake forms and sync demographic data with the EHR.

Patient Intake & Registration

Demographic sync

Insurance verification

Document collection

Enable online booking and schedule management integrated with the EHR.

Appointment Scheduling

Online booking

Waitlist & reminders

Deliver lab and diagnostic results to the EHR and notify providers.

Lab Results Integration

Results delivery

Order tracking

Results write-back

Share patient records across providers for referrals and transitions of care.

Care Coordination

Referral management

Records exchange

Capture device-generated vitals and observations and push them into the patient chart.

Remote Patient Monitoring

Vitals sync

Vitals write-back

Alert-based workflow

Automate charge capture, claims submission, and payment posting.

Revenue Cycle Management

Charge capture

Eligibility check

Claims & payments

Extract and analyze patient data across populations for quality measures and risk stratification.

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