How OpenCall Shipped a Production Calendar Agent in Under an Hour With Midpoint
1) Tech Debt Turns “Simple Agents” Into Slow Shipping
OpenCall came to Midpoint with a common AI-native problem: the agent logic was ready, but the execution layer was not. They had an internal Google Calendar implementation with significant tech debt and no one to maintain it, which meant every “small change” became a project. They needed a production-grade API to check availability and book meetings, and they needed it to run reliably on their landing page without constant babysitting. What used to take weeks of development and debugging was completed in under an hour, and the agent went live immediately.
2) The Midpoint Pattern: Google Calendar → Availability API → Booking → Live Agent
Midpoint turned OpenCall’s calendar requirements into an end-to-end workflow: connect Google Calendar with OAuth, define availability rules, expose a clean interface the agent could call, and write back confirmed bookings. The result was a Calendar workflow that behaves like a maintained product, not a one-off integration. OpenCall’s agent simply calls the API to check availability and book. Midpoint handles the wiring, step logic, and deployment so the team can ship faster without carrying the maintenance burden.
3) Exception Handling Is the Product
Calendar workflows fail in edge cases, not the happy path. Double bookings, time zone ambiguity, missing attendee context, conflicts with existing events, and policy constraints like buffers and working hours are where DIY implementations rot. Midpoint bakes exceptions into the workflow: conflict detection, safe fallbacks, validation checks, and human handoff when the agent is uncertain. That’s how OpenCall avoided shipping an agent that works in demos but breaks in production.
4) Reliability: Monitoring, Alerts, and Audit Trails
OpenCall didn’t just need a calendar agent. They needed confidence it would keep running. Midpoint adds observability: a Dashboard view of executions, traceable logs for what happened and why, and alerts when something fails so problems don’t become silent revenue leaks. If Google Calendar throws transient errors or auth needs refresh, retries and recovery keep the workflow stable. When something changes, Midpoint can ship fixes quickly rather than forcing OpenCall to reopen an old codebase and untangle it again.
5) Expand It Into a Full Growth OS: Prospecting + Inbox Routing
Once the calendar agent was live, the bigger operational win was building repeatable automations across OpenCall’s growth stack. Midpoint deployed two core workflows: Prospect Miner and Inbox Router. Prospect Miner takes a target company list from Google Sheets, performs enrichment and scoring using AI and web signals, then pushes clean records into HubSpot with owners, lifecycle stages, and tasks. Inbox Router triages inbound Gmail threads, labels intent, updates HubSpot automatically, and alerts the right owner when urgency is high. The impact was immediate: lead research time dropped by over 80%, high-intent response time fell from hours to under 15 minutes, and OpenCall reclaimed roughly 129 hours per month previously lost to manual admin work.
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