Original Summary

Hey r/SideProject ! 👋 Like many hobby collectors and parents, I spent way too many Saturday mornings driving 45 minutes between local Targets, Walmarts, and GameStops hoping to find sealed Pokémon cards at MSRP—only to stare at picked-over shelves or miss a vendor restock by 20 minutes. Big-box retailers don’t show this inventory on their apps or websites because third-party distributors (MJ Holding, Excell) stock the shelves independently of the retailer's inventory feeds. The only way to know if product is physically sitting on the counter is to ask an employee. So over the past few months, I built AlreadyCalled : an automated AI voice agent that dials local big-box stores, navigates their automated PBX phone trees, speaks conversationally with the department clerk, and transcribes verified inventory findings before you start your car. We just crossed 1,000 completed calls across 14 major retail chains. Here’s a breakdown of how it works, the tech stack, and the wild telephony edge cases we ran into. How It Works Under the Hood: ZIP Directory Search: The user enters a 5-digit ZIP code. The app geocodes the area and queries our mapped catalog of retail stores (Target, Walmart, Barnes & Noble, Walgreens, CVS, Dollar Tree, etc.). Telephony Dispatch: The backend reserves a call slot, checks rate limits and active store cooldowns, and dispatches a low-latency SIP call via Retell AI + Twilio. Automated Phone Tree Navigation: Every retail chain has a unique IVR. The agent injects dynamic DTMF tones (keypad digits) to bypass corporate automated menus and route to the right department. Conversational AI & Compliance: The agent introduces itself, states mandatory two-party recording / AI disclosure greetings required by state law, and asks the clerk a polite, 5-second question about specific sealed product. Real-Time Classification & Cooldown: Retell's post-call LLM analyzes the audio transcript, scores in-stock status, and marks the store with a 4-hour community cooldown so no store gets repeatedly spammed by other users. Voicemail / Busy Protection: If the line is busy, disconnects, or hits voicemail, the user’s call allowance is instantly refunded and up to 3 automatic retries are scheduled. The Tech Stack: Frontend: Next.js 16 (App Router), Tailwind CSS, React Server Components Telephony / Voice: Retell AI + Twilio SIP trunking Backend / Database: Google Cloud Run, Firebase Firestore, Cloud Functions Maps & Discovery: Google Places Text Search (heavily cached per chain to control API costs) Auth & State: Firebase Auth Telephony Lessons Learned the Hard Way: Most AI demos are basic chat wrappers. Connecting an LLM to the real-world telephone network surfaces weird bugs you’d never anticipate: The 2-Second Audio Path Delay: When a PSTN call connects, the analog audio stream takes 1.5 to 2.5 seconds to fully initialize. If your voice model speaks immediately upon connection, the store's automated greeting cuts off the fi

  • 情报分类：商业与市场研究
  • 分类依据：内容涉及商业、投资或市场动态
  • 信息来源：Reddit · SideProject
  • 发布时间：2026/9/18 23:41:30