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Karbon HQAPIintegration&MCPserver

Deliver real-time HR & Directory faster, close sales deals sooner, and scale without an integration backlog.

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Add Karbon HQ and 79 other pre-built HR & Directory integrations

Real-time data to fuel countless HR use cases

Power AI copilots, insights, predictive analysis, and automation with a modern integration infrastructure that scales alongside you.

hris

Onboarding

Onboard employees and update profiles when roles change.

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hris

Offboarding

Seamlessly integrate employee data to automate the offboarding processess.

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hris

Track PTO

Pull time off (PTO) information to monitor and manage employee leave balances and schedules in real-time.

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Unified MCP

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HRIS Employee

HRIS Company

Passthrough

HRIS Employee

HRIS Company

Passthrough

Your customer's data

on Karbon HQ

Unified API data-models and methods

HRIS Employee

list get create

HRIS Company

list get create update

Passthrough

get post put patch delete

79 Unified MCP tools

create an employee32 parameters

list all employees3 parameters

retrieve an employee2 parameters

create a company4 parameters

list all companies3 parameters

retrieve a company2 parameters

update a company5 parameters

get a list of integration task definitions

get a list of integration tasks2 parameters

get an integration task details2 parameters

update an integration task11 parameters

gets a list of invoices3 parameters

gets a single invoice3 parameters

gets a list of payments2 parameters

create a manual payment against an invoice

delete a manual payment2 parameters

reverse a manual payment

gets a single payment2 parameters

gets a single business card2 parameters

updates a single business card15 parameters

gets a list of client groups4 parameters

creates a new client group12 parameters

gets a client group using userdefinedidentifier3 parameters

gets a client group using clientgroupkey3 parameters

updates a client group (full)12 parameters

updates a client group (partial)3 parameters

gets a comment using commentkey2 parameters

gets a list of contacts4 parameters

creates a new contact15 parameters

gets a contact using userdefinedidentifier3 parameters

gets a contact using contactkey3 parameters

updates a contact (full)17 parameters

updates a contact (partial)8 parameters

gets all custom field definitions for the current tenant

creates a new custom field definition5 parameters

deletes a custom field definition by key2 parameters

gets custom field values for a specific entity2 parameters

updates custom field values for a specific entity4 parameters

gets estimate summaries using workitemkey2 parameters

uploads and links a file8 parameters

get a file using it's token 1 parameter

get a list of files for a given entity3 parameters

gets a note using noteid2 parameters

creates a new note7 parameters

gets a list of organizations4 parameters

creates a new organization10 parameters

gets an organization using userdefinedidentifier3 parameters

gets an organization using organizationkey3 parameters

updates an organization (full)12 parameters

updates an organization (partial)4 parameters

assigns one or more tags to an entity3 parameters

removes one or more tags to an entity2 parameters

gets lists of customer specific contact and work settings

gets a list of timesheets5 parameters

gets a timesheets using timesheetkey3 parameters

gets a list of users3 parameters

creates a new user2 parameters

gets the details of a single user2 parameters

gets a webhook subscription2 parameters

deletes a webhook subscription2 parameters

creates a new webhook subscription3 parameters

deletes all webhook subscriptions

gets a list of work items4 parameters

creates a new work item17 parameters

gets a work item using workitemkey2 parameters

updates a work item (full)19 parameters

updates a work item (partial)2 parameters

creates a new work schedule15 parameters

gets a work schedule using workschedulekey2 parameters

updates a work schedule (full)18 parameters

gets a list of work templates4 parameters

gets a work template using worktemplatekey2 parameters

contact created or updated4 parameters

estimate summary updated4 parameters

integration task created7 parameters

invoice status updated4 parameters

note created or updated4 parameters

user has accepted karbon invite4 parameters

work created or updated4 parameters

The modern Unified API platform, built differently

Real-time, pass-through

Every request hits the source API live. No caching, no sync jobs, no stale data — just on-demand API reads/writes with native and virtual webhooks for instant updates.

Zero-storage by design

We never store end-customer data. Traffic is stateless and regionalized (US/EU/AU), reducing compliance scope and eliminating data-at-rest risk.

One API, deeply normalized

370+ integrations, 24 categories... Unified objects, endpoints, scopes, and errors—plus raw payload passthrough when you need provider-specific fields.

Custom fields & objects

Go beyond shallow schemas. We support custom fields and read/write on custom objects (e.g., Salesforce) via unified metadata APIs.

AI-ready integrations

Built for AI products: real-time streams for RAG/embeddings and Unified MCP tools that securely grant LLMs controlled integration access.

Predictable pricing, no lock-in

Transparent usage-based pricing that scales with API volume—not customers. Own your credentials and migrate anytime.

Add a Karbon HQ integration to your application in hours

1Test drive integrations

Effortlessly test API calls, explore endpoints, and try out the Karbon HQ integration using synthetic data in our Sandbox environment.

2Authorize connections

Drop in our Authorization component with a single line of code. Your users can then connect and grant access to their Karbon HQ data.

3Start making API calls

Use the Connection ID to interact with Karbon HQ via our unified API. We handle maintenance and updates so you can focus on your product.

Seamless Auth, no extra work

Unified.to removes the complexity of authentication and authorization so you can focus on building your product, not managing auth flows. Our pre-built UI and flexible API handle everything in the background—no extra setup required.

See documentation

React

React component React component source code

Trusted by global product companies and developers to power integrations for innovative AI and SaaS applications

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Integrate with all the major hr & directory applications

Unified.to makes it possible to integrate once to a unified API to connect with all the applications your customers use, so you can train AI models, build advanced automation, and expand your market.

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