HR, payroll and shifts
Connect Paychex Flex to Hypamoon
Possible, with help from Paychex Flex. The API is documented, but you cannot just create a key: access goes through Paychex Flex first.
PossibleThe check
Three questions about the API of Paychex Flex, answered from its own docs.
- Public API docs
- Yes. Read the docs
- A key you create yourself
- No. Access starts with a questionnaire for the Paychex partnerships team; after approval Paychex creates the application and issues a key and secret, and each client must approve the app in Paychex Flex. developer.paychex.com
- Versions or a changelog
- Not confirmed. The docs have a versioning section that could not be read.
- How it signs in
- OAuth 2.0 with a key and secret that Paychex issues to an approved application, combined with access granted by each client.
- Webhooks
- Yes. It can tell your app when something changes. developer.paychex.com
- Hosting
- Cloud
- Condition
- API keys are only issued after an application to and approval by the Paychex partnerships team.
What you can build
Read workers and pay data for reporting, or send hours into payroll, once Paychex has approved the integration.
Your chat writes it as a Hypamoon adapter from the docs above. Reading starts after you click Allow in the portal, and every write waits for your approval, one call at a time. How adapters work
Good to know
- Paychex Flex signs in with OAuth or signed requests only, with tokens that expire. The Hypamoon vault holds a fixed key today, so an adapter for Paychex Flex takes more work: ask your chat to check this first.
- Paychex asks for a demo of the finished integration before final approval.
Try it in your chat
First get access from Paychex Flex. Then fill in what to read and write, and send it.
Build the Hypamoon recipe build-an-adapter for Paychex Flex. API docs: https://developer.paychex.com/resources/overview. Read: [what]. Write: [what, or nothing].
In Claude, or another chat with the full Hypamoon connection; adapters are not in ChatGPT yet. You paste the key in the portal, never in the chat. The full recipe
Sources
Checked on 1 November 2026.
Paychex Flex is a name of its owner, used here only to describe the software. This page is not an official integration and Hypamoon has no partnership with Paychex Flex. Found something that changed? Tell us at support.
Tool not listed? Ask the chat to check its API.
The same three checks work for any software. Your chat reads the vendor's own docs and tells you what it found.
Check if [software] has an open API that a Hypamoon adapter can use: public API docs, a key or token I can create myself without asking the vendor, and versions or a changelog. Link the pages you used.
Fill in the name of your software. Checking needs no connection to Hypamoon.
Ready to connect Paychex Flex?
Connect your chat once, then ask it to build the adapter.
Works in Claude and ChatGPT. Add to Claude Add to ChatGPT