Simployer One MCP Server
for AI Agents
Connect your AI agent to StackOne's Simployer One MCP server and give it 55 MCP tools out of the box. Auth, tool execution, and security all managed.
StackOne 
Coverage
55 Agent Actions
Create, read, update, and delete across Simployer One — and extend your agent's capabilities with custom actions.
Authentication
Agent Tool Authentication
Per-user OAuth in one call. Your Simployer One MCP server gets session-scoped tokens with zero credentials stored on your infra.
Agent Auth →
Security
Agent Protection
Every Simployer One tool response scanned for prompt injection in milliseconds — 88.7% accuracy, all running on CPU.
Prompt Injection Defense →
Performance
Max Agent Context. Min Cost.
Free up to 96% of your agent's context window to enhance reasoning and reduce cost, on every Simployer One call.
Tools Discovery →What is the Simployer One MCP Server?
A Simployer One MCP server lets AI agents read and write Simployer One data through the Model Context Protocol — Anthropic's open standard for connecting LLMs to external tools. StackOne's Simployer One MCP server ships with 55 pre-built actions, fully extensible via the Connector Builder — plus managed authentication, prompt injection defense, observability, and agent execution runtime. Connect it from MCP clients like Claude Desktop, Claude Code, Cursor, Goose, and VS Code, or from agent frameworks like OpenAI Agents SDK, LangChain, and Vercel AI SDK.
All Simployer One MCP Tools
Every action from Simployer One's API, ready for your agent. Create, read, update, and delete — scoped to exactly what you need.
Companies
- List Companies
Retrieve a list of all companies in the Simployer account
Companys
- Get Company
Retrieve a specific company by its ID
Compensations
- Create Compensation
Create a new compensation record
- List Compensations
Retrieve a list of all compensations
- Get Compensation
Retrieve a specific compensation by its ID
- Update Compensation
Update an existing compensation record
- Delete Compensation
Delete a compensation record by its ID
Cost Centers
- Create Cost Center
Create a new cost center
- List Cost Centers
Retrieve a list of all cost centers
- Get Cost Center
Retrieve a specific cost center by its ID
- Update Cost Center
Update an existing cost center
- Delete Cost Center
Delete a cost center by its ID
Departments
- Create Department
Create a new department
- List Departments
Retrieve a list of all departments
- Get Department
Retrieve a specific department by its ID
- Update Department
Update an existing department
- Delete Department
Delete a department by its ID
Employees
- Create Employee
Create a new employee
- List Employees
Retrieve a list of all employees
- Get Employee
Retrieve a specific employee by their ID
- Update Employee
Update an existing employee
- Delete Employee
Delete an employee by their ID
Employment Types
- Create Employment Type
Create a new employment type
- List Employment Types
Retrieve a list of all employment types
- Get Employment Type
Retrieve a specific employment type by its ID
- Update Employment Type
Update an existing employment type
- Delete Employment Type
Delete an employment type by its ID
Employments
- Create Employment
Create a new employment record
- List Employments
Retrieve a list of all employments
- Get Employment
Retrieve a specific employment by its ID
- Update Employment
Update an existing employment record
- Delete Employment
Delete an employment record by its ID
Leave Types
- Create Leave Type
Create a new leave type
- List Leave Types
Retrieve a list of all leave types
- Get Leave Type
Retrieve a specific leave type by its ID
- Update Leave Type
Update an existing leave type
- Delete Leave Type
Delete a leave type by its ID
Leaves
- Create Leave
Create a new leave request
- List Leaves
Retrieve a list of all leaves
- Get Leave
Retrieve a specific leave by its ID
- Update Leave
Update an existing leave request
- Delete Leave
Delete a leave request by its ID
Offices
- Create Office
Create a new office
- List Offices
Retrieve a list of all offices
- Get Office
Retrieve a specific office by its ID
Projects
- Create Project
Create a new project
- List Projects
Retrieve a list of all projects
- Get Project
Retrieve a specific project by its ID
- Update Project
Update an existing project
- Delete Project
Delete a project by its ID
Teams
- Create Team
Create a new team
- List Teams
Retrieve a list of all teams
- Get Team
Retrieve a specific team by its ID
- Update Team
Update an existing team
- Delete Team
Delete a team by its ID
Simployer One AI Agent Use Cases
Connect your AI agent to Simployer One and help your team scale the HR operations they run by hand today.
Use StackOne to connect your AI agent to your HRIS, identity management, and LMS to automate employee onboarding.
ViewUse StackOne to connect your AI agent to your HRIS, knowledge base, and messaging tools to automate HR policy Q&A.
ViewUse StackOne to connect your AI agent to your HRIS, identity management, and ITSM to automate employee offboarding and deprovisioning.
ViewSet Up Your Simployer One MCP Server in Minutes
One endpoint. Any framework. Your agent is talking to Simployer One in under 10 lines of code.
Agent Frameworks
JSON{
"mcpServers": {
"stackone": {
"command": "npx",
"args": [
"-y",
"mcp-remote@latest",
"https://api.stackone.com/mcp?x-account-id=<account_id>",
"--header",
"Authorization: Basic <YOUR_BASE64_TOKEN>"
]
}
}
}Check More HRIS / HCM MCP Servers
139+ actions
128+ actions
127+ actions
123+ actions
120+ actions
117+ actions
111+ actions
Platform Resources
MCP Code Mode: Keeping Tool Responses Out of Agent Context
Anthropic's code_execution processes data already in context. Custom MCP code mode keeps raw tool responses in a sandbox. 14K tokens vs 500.
11 min
Comparing BM25, TF-IDF, and Hybrid Search for MCP Tool Discovery
Benchmarking BM25, TF-IDF, and hybrid search for MCP tool discovery across 916 tools. The 80/20 TF-IDF/BM25 hybrid hits 21% Top-1 accuracy in under 1ms.
10 min
Indirect Prompt Injection Defense for MCP Tools: A Technical Guide
MCP tools that read emails, CRM records, and tickets are indirect prompt injection vectors. Here's how we built a two-tier defense that scans tool results in ~11ms.
12 min
MCP vs A2A: Architecture, Security, and When to Use Each
MCP vs A2A: what each protocol standardizes, how they differ, their shared security risks including indirect prompt injection, and when to use one, both, or a hybrid architecture.
12 min
MCP vs API: What 200+ Connector Builds Taught Us
MCP wraps APIs, it doesn't replace them. After building 200+ connectors that serve both, here's when each approach wins.
14 min read
Simployer One MCP Server FAQ
Does StackOne have a Simployer One MCP server?
Simployer One MCP server vs direct API integration — what's the difference?
How does Simployer One authentication work for AI agents?
origin_owner_id.Are Simployer One MCP tools vulnerable to prompt injection?
What is the context bloat of a Simployer One agent and how do I avoid it?
Can I limit which actions my Simployer One agent can access?
Can I create custom agent actions for my Simployer One MCP server?
When should I NOT use a Simployer One MCP server?
What AI frameworks and AI clients does the StackOne Simployer One MCP server support?
Put your AI agents to work
All the tools you need to build and scale AI agent integrations, with best-in-class connectivity, execution, and security.