Gusto
Payroll, benefits and HRUS payroll, benefits and HR for small businesses. Its MCP server brings live payroll and people data into AI tools, with per-category permissions and confirmation before any write.
MCPAPI/CLIBulk import
Ops
J
Justworks
PEO and payroll Ops API/CLIBulk import
Independent review. IonBin has no partnership with Justworks and was not paid for this page. Our evaluation is our own, based on public documentation and our research. Product names are trademarks of their owners and are used for identification only. How disclosure works.
A professional employer organization (PEO) and payroll provider for US teams, with an employer-of-record option for hiring abroad. Integrations use a Partner API for approved partners; no official MCP server found.
Not advice
IonBin provides general information and software comparisons, not tax, legal, accounting or financial advice. Tax and legal rules vary by situation and jurisdiction; consult a qualified professional (CPA, enrolled agent or attorney) before acting.
AI tools can make mistakes. Verify every figure against the original documents and official IRS or state guidance before filing or signing.
Redact Social Security numbers, account numbers and EINs before uploading documents to any AI assistant, and check its data-retention settings. Upload originals only to the filing or signing software.
Best for
- Small US teams that want PEO benefits
Not for
- Teams that only need payroll
Top use cases
- Run US payroll and HR, with or without PEO benefits source ↗
- Upload bulk payments from a file source ↗
In depth
Plans
Justworks lists Payroll ($8 per employee/month plus a $50/month base fee), PEO Basic ($79 per employee/month, no base fee), PEO Plus ($124, adds medical, dental and vision administration) and EOR for international hires ($599 per employee/month). Add-ons include time tracking ($8 per employee/month) and international contractors ($39 per paid contractor/month). Checked 2026-10-17. source ↗
How to use it with AI
How Justworks connects to each AI platform: native connector or MCP, API through code the agent writes, browser control, or file upload.
| Platform | MCP / connector | API (agent-written code) | Browser | Upload / export |
|---|---|---|---|---|
| Claude (incl. Claude Code) | No documented route | Confirmed Claude (incl. Claude Code) can run code; Justworks publishes an API. Justworks API ↗Claude (incl. Claude Code) docs ↗ | Confirmed Claude Code with the Claude in Chrome extension (Chrome, Edge and other Chromium browsers) Claude (incl. Claude Code) browser docs ↗ | Confirmed Export from Justworks, then works on the files in your project; chat accepts attachments Claude (incl. Claude Code) docs ↗ |
| OpenAI Codex | No documented route | Confirmed OpenAI Codex can run code; Justworks publishes an API. Justworks API ↗OpenAI Codex docs ↗ | Confirmed Only in the ChatGPT desktop app; not in the Codex CLI or IDE extension OpenAI Codex browser docs ↗ | Confirmed Export from Justworks, then works on local repositories OpenAI Codex docs ↗ |
| Google Antigravity | No documented route | Confirmed Google Antigravity can run code; Justworks publishes an API. Justworks API ↗Google Antigravity docs ↗ | Confirmed Browser subagent via /browser, documented as an Antigravity App feature; the IDE has separate browser docs Google Antigravity browser docs ↗ | Confirmed Export from Justworks, then works on local projects and worktrees Google Antigravity docs ↗ |
Confirmed means both the tool's and the platform's official docs describe that route (links in the cell); IonBin has not tested every pairing. Not documented means it may work, but no official docs describe that route end to end. Checked Oct 17, 2026.
Agent compatibility
API/CLIBulk import
| Level | Status | Detail / source |
|---|---|---|
| Native connector / MCP | No | No official MCP server found (2026-10-17) |
| API / CLI | Yes | Official docs ↗ |
| Browser-only | No | Web app; also reachable programmatically |
| Bulk upload / import | Yes | Bulk updates and CSV payment uploads for existing employees (https://help.justworks.com/hc/en-us/articles/11308602181659-Bulk-Updates-Center) |
Recorded Oct 17, 2026. Setup and plan limits vary; check the vendor's docs. How levels are assigned.
Works well with
Connects to agent platforms
No confirmed MCP server yet.
Via its API, through automation hubs: Gumloop, Make, n8n, Zapier.
Workflows using this tool
- Decide between a PEO and payroll-only Reviewed
- Write benefits enrolment messages for HR approval Reviewed
Review
No long-form review yet. Verdict is based on research, not hands-on testing.
Alternatives
OnPay
Payroll and HRPayroll, HR and benefits for US small businesses, with tax filings and year-end forms included. Its API is limited to approved partners; no official MCP server found.
API/CLIBulk import
Ops
Rippling
HR, IT and finance platformCombines HR, payroll, device and app management in one system. Rippling MCP connects Claude, ChatGPT and other AI tools to company data within each user's Rippling permissions; it needs a Rippling AI subscription and admin-granted access.
MCPAPI/CLIBulk import
Ops