Customer Spotlight: Scaling the Penciled Agent with Real-Time EHR Integrations

By Richard Zhang | May 15, 2025

I’m Richard, co-founder of Integuru. We build integrations with platforms that lack official APIs. We integrate with many healthcare platforms, namely electronic health records (EHRs) and electronic medical records (EMRs).

For messaging-based and voice-based products, latency and reliability aren’t just nice-to-haves but necessities. These requirements are especially true in healthcare, where a 30-second delay or a missed appointment can break patient trust, disrupt operations, and lead to lost revenue.

Penciled faced these latency and reliability problems. They’re an Initialized-backed healthcare startup building a messaging agent for physical therapy (PT) clinics. Their product helps clinics handle patient messages automatically, schedule appointments, manage cancellations, and perform patient intake. However, as their user base grew, their integrations with electronic health record (EHR) systems couldn’t keep up.

They solved that by using Integuru to move from fragile scripts to fast and reliable integrations. The result was more confident patients, stronger infrastructure, and direct revenue growth.

The Integration Problem: Frontend Scripts and Latency Walls

When EHRs lack official or adequate APIs, Penciled’s initial integrations were built using browser automation. After patients contacted the clinic, the Penciled agent triggered a headless browser, loaded the clinic’s EHR system, and interacted with the frontend to complete actions like booking appointments or fetching availability.

This approach worked, but only for a while. Two problems stood out in particular:

1. Breakage from UI Changes

EHR systems change their frontends often. A slight layout shift or class name update would break the automation scripts. Engineers had to go in and fix things manually every time this happened. That led to frequent errors, downtime, and operational stress.

2. Latency from Page Loads

Even when it worked, browser automation was slow. Each action required the page to fully load before the next step could begin. For messaging interactions, this meant wait times of 30–40 seconds per task, which is far too long for a real-time conversation with a patient.

To reduce this, Penciled cached appointment data every ~30 minutes. But caching introduced a different problem: what if two patients tried to book the same slot before the cache refreshed? That meant real-world scheduling issues and a bad experience for everyone involved.

At this point, Penciled knew they needed something better. That’s when they came to Integuru.

The Fix: Reverse-Engineering Internal APIs

Instead of working through the frontend, Integuru helped Penciled move to internal API connections. This new approach means skipping the browser and sending requests directly to the backend systems powering each EHR platform.

Every modern web app has internal APIs. The frontend uses these hidden endpoints to communicate with the backend. Penciled could achieve fast, direct access to the needed scheduling and patient data by reverse-engineering these APIs.

At Integuru, we support this process end-to-end. We provide AI tooling and services to analyze network requests, decode authentication flows, and generate integration code for internal APIs. We make the final integration as easy and reliable to use as a public API.

The Result: Sub-Day Setup, Real-Time Usage

Once the integrations were ready, Penciled’s team implemented them in production in less than one day per integration. The difference was immediate:

• 99%+ Uptime: The internal APIs proved far more stable than the frontend, reducing breakages to near-zero.
• Real-Time Responses: On average, actions that used to take 30+ seconds now complete in 3 seconds. 

Penciled no longer needs to cache appointment data; they can now pull it in real-time for maximum accuracy. And most importantly, customers were happier. Clinics could trust the messaging agent to get things done. That trust translated into new customers and more revenue for Penciled.

Beyond the numbers, the Penciled team now has confidence that their infrastructure won’t break during patient interaction. They never wake up worrying about breakages or bottlenecks. They could focus on growing the product instead of putting out fires.

Why Not Just Build In-House?

This is a question we hear often. If internal APIs are better, why not build those integrations yourself?

Penciled considered that too. But the reality is, building the integration is only half the job. You also have to maintain it. That means having engineers on-call around the clock, keeping tooling up to date, reversing new API changes as they come up, and debugging issues that surface when systems update without warning.

Creating and maintaining integrations are both full-time jobs. If you’re deciding whether to build it in-house or outsource, you have to ask yourself: Do you have the engineers, the tooling, and the expertise to do this reliably? Integuru does.

Working with Integuru freed up Penciled’s engineering time. They now focus on building the product, while we handle the connections behind the scenes.

The Bigger Picture

Today, many of Integuru’s customers are agentic products like Penciled. These products depend on integrations working reliably across third-party platforms.

When latency or reliability becomes a bottleneck, internal APIs are the path forward. And our goal is to make that path fast, affordable, and simple, without sacrificing capability.

Contact Us

Let's talk if you’re working on a product that needs to connect to external platforms.

Book a call with us to get started.