Fourth

Live 29 Actions

Fourth integration for AI agents

Connect your AI agent to 29 production-ready Fourth actions via MCP, A2A, or SDK — with managed agent tool auth, optimized execution, and built-in security.

Start Free Book Demo Fourth MCP Server

Fourth AI agent actions

29 production-ready actions for your agent to do more on Fourth.

Start Free Book a Demo Fourth MCP server

Watch Employee Onboarding Demo

29 Actions

List Employees - Get a list of employees for the organisation

Create Employee - Create a new employee in Fourth

Update Employee - Update an existing employee in Fourth

List Employee Sources - Get a list of recruitment sources

List Absences - Get absences for employees

Create Absence - Create an absence record for an employee

Update Absence - Update an existing absence record

Delete Absence - Delete an absence record for an employee

List Employments - Get employment details for employees

List Multiple Employments - Get multiple employments for a specific employee

Create Multiple Employment - Create a multiple employment record for an employee

List Addresses - Get addresses for employees

List Dependents - Get dependents for employees

List Next Of Kin - Get next of kin details for employees

List Passports - Get passport details for employees

List Country Specific Fields - Get country-specific fields for employees

List Holiday Accrual - Get current holiday accrual for flexible employees

List Divisions - Get divisions for the organisation

List Locations - Get locations for the organisation

Create Holiday - Create a holiday request for an employee

Delete Holiday - Delete a holiday request for an employee

List Payment Details - Get payment details for employees

Create Payment Details - Import employee payment details

List Payslips - Get payslip details for employees

List Pay Parts - Get shift details for a pay period

List Payroll Periods - Get payroll periods for the organisation

Get Pay Parts Export - Get pay parts export for a specific pay period

Get Pay Parts Export By Employee - Get pay parts export for a specific employee in a pay period

Get Post Pay-Run Export - Get post pay-run export for a specific pay period

Do More, Build Less.

Integration Infrastructure for Fourth AI Agents.

Multiple Interfaces

Access integrations via API, AI SDKs, MCP & A2A.

Fourth MCP server

Managed Authentication

Pre-built authentication UI.

Agent auth

Falcon Engine

Every Fourth action runs on Falcon.

Agent Execution Engine

StackOne Defender

88.7% prompt injection detection.

Prompt injection defense

"What impressed us most about StackOne is its ambition and clarity. They're creating infrastructure that modern software and the entire AI agent ecosystem can rely on. The depth of secure integrations, the pace of delivery, and the team's foresight into AI's future uniquely position StackOne to redefine this category."

Luna Schmid, Partner at GV

"We've been impressed by how quickly and deeply StackOne integrates with complex enterprise systems -- and now, with their focus on agent-to-agent interoperability, they're unlocking even more powerful use cases for customers. StackOne delivers all of the above in a universal layer -- without compromise."