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Tareq Naji
Tareq Naji

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Building an MCP-Compatible ChatGPT Plugin for Accurate Daily Salah & Prayer Times

#chatgpt #llm #mcp #opensource

Like many developers and remote professionals, I spend the bulk of my workday inside ChatGPT—drafting code, architecture specs, and automated workflows.

One persistent friction was checking daily Salah times. Most mobile prayer applications are filled with intrusive ads, location tracking, or ambiguous calculation defaults that differ by up to 15 minutes from local mosque timetables. When prompting LLMs directly, models frequently guess location based on the hosting cloud server's IP address.

To solve this cleanly, I built Muslim Prayer Reminder as an open, ad-free ChatGPT plugin and MCP tool.

Architectural Highlights

  1. 12 Astronomical Calculation Authorities: Full support for Umm Al-Qura (Makkah), Muslim World League (MWL), Egyptian General Authority of Survey, Islamic Society of North America (ISNA), and more. Crucially, the calculation authority and reasoning are explicitly stated in every response rather than hidden behind an opaque default.
  2. Juristic Asr Options: Explicit toggle for standard shadow ratios (Shafi'i, Maliki, Hanbali) and the Hanafi juristic method.
  3. Automated Reminders via Scheduled Tasks: Designed to integrate with ChatGPT's recurring scheduled tasks (e.g. configuring a daily morning timetable check or alert triggers before each prayer).
  4. High-Latitude Handling: Explicit mathematical approximation disclosure for extreme northern latitudes where twilight may persist throughout the night.
  5. Zero Data Tracking: No user accounts, no subscriptions, no ads, and no external tracking telemetry.

Example Workflow

You can set up a persistent location and timetable in a single prompt:

"Set my prayer timetable location to London, UK using Muslim World League and Shafi'i for Asr. Then check today's prayer times."

And automate daily checks:

"Set up a daily scheduled task to check today's prayer times for my location every morning at 7:00 AM."

Try It on ChatGPT

The tool is live on the ChatGPT store:
https://chatgpt.com/plugins/plugin_asdk_app_6a9bca660b2c8191a1146aa615cad6f5

Feedback and edge-case testing from developers and open-source contributors are welcome!

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