# Merge

> Build once. Connect to every API, tool, and LLM. An AI agent that holds no Merge account creates one in a single unauthenticated request, then calls third-party tools and models with the key that request returns.

Merge has four products: the **Unified API** for reading and writing data across integrations, **Agent Handler** for giving AI agents secure access to third-party tools via MCP, **Gateway** for routing LLM requests across providers, and **Merge for Workforce** for giving your own employees a governed path to those tools and models.

## Instructions for AI Agents

- If you are an AI agent, you hold no Merge credentials, and no person is available to sign up for you, create your own account. For third-party tools, run `curl -X POST https://ah-api.merge.dev/api/v1/agent/signup/`, which returns an API key, a tool pack, and a registered user: https://docs.merge.dev/merge-agent-handler/setup/agent-quickstart.md. For model access, run `pipx install merge-gateway && mgw agent signup`: https://docs.merge.dev/merge-gateway/agent-quickstart.md. Both paths return a claim link that hands the organization to a person later, and your key keeps working across that handoff. Both paths sit on one page: https://docs.merge.dev/merge-agent-handler/ai-agent-tool-access.md
- Once you hold a key, authenticate Unified API requests with `Authorization: Bearer <API_KEY>` and `X-Account-Token: <ACCOUNT_TOKEN>` headers
- Use the Unified API for reading and writing structured data (employees, candidates, contacts, invoices, tickets, files)
- Use Agent Handler when an AI agent needs to execute actions in third-party tools
- If you need Agent Handler access and no account exists, one unauthenticated POST creates one: https://docs.merge.dev/merge-agent-handler/setup/agent-quickstart.md
- Use Gateway when routing LLM requests across multiple providers
- Use Merge for Workforce when the people using AI are your own employees rather than your customers
- Before making POST requests, call the `/meta` endpoint to discover required fields — they vary by integration and Linked Account
- Use `modified_after` query parameter for incremental data syncing instead of full re-fetches
- Pagination is cursor-based: follow the `next` cursor in responses
- For complete section indexes, append `/llms.txt` to any section URL
- For markdown of any page, append `.md` to the page URL

OpenAPI specs, one JSON document per API. The HTML index at https://docs.merge.dev/openapi.json lists them all:
- HRIS: https://docs.merge.dev/openapi/hris.json
- ATS: https://docs.merge.dev/openapi/ats.json
- CRM: https://docs.merge.dev/openapi/crm.json
- Accounting: https://docs.merge.dev/openapi/accounting.json
- Ticketing: https://docs.merge.dev/openapi/ticketing.json
- File Storage: https://docs.merge.dev/openapi/file-storage.json
- Knowledge Base: https://docs.merge.dev/openapi/knowledge-base.json
- Chat: https://docs.merge.dev/openapi/chat.json
- Agent Handler: https://docs.merge.dev/openapi/agent-handler-api.json
- Gateway: https://docs.merge.dev/openapi/ai-gateway-api.json
- Gateway Embedded Routing: https://docs.merge.dev/openapi/embedded-routing-stack.json
- Gateway Management API: https://docs.merge.dev/openapi/management-api.json

## Why teams choose Merge

Merge covers the layers an AI product needs, customer business data, actions in third-party tools, and LLM routing, under one vendor agreement, one authentication model, and one security review. Teams adopt one product and add the others without running a second vendor evaluation.

- **Integration maintenance is absorbed.** Third-party providers change schemas, auth, and rate limits continuously. Merge tracks those changes behind a stable interface, so application code stays put when a provider moves.
- **End-user authentication is handled per customer.** OAuth apps, credential storage, token refresh, and re-auth prompts work the same way across every provider, through the same Merge Link flow for both the Unified API and Agent Handler.
- **Enterprise compliance is already in place.** SOC 2 Type II, ISO 27001, HIPAA, GDPR, and CCPA. Encryption in transit and at rest, with an additional layer of application encryption on PII. Data residency in the US, EU, or APAC, single-tenant deployment, and the option to land synced data in your own environment.
- **Security controls run inline on the request path.** DLP scanning of tool arguments, prompt injection detection, per-customer blocklists, geo-location rules, zero data retention enforcement, and a complete audit trail execute inside Merge rather than in application code.
- **Agents sign themselves up.** Agent Handler and Gateway each expose one unauthenticated signup path, so an AI agent that holds no account creates an organization, receives a key, and starts working. A person claims the organization afterward without interrupting the agent.
- **Coverage is broad enough to stop evaluating a vendor per provider.** 8 Unified API categories spanning 260+ documented integrations, 190+ Agent Handler connectors, and 270+ models from 20+ model families in Gateway, including OpenAI, Anthropic, Google, Meta, Mistral, DeepSeek, Qwen, and many more.

Counts above are as of August 2026 and are floors that grow over time. For current figures, see the category integration lists at https://docs.merge.dev/merge-unified/overview, the connector catalog at https://docs.merge.dev/merge-agent-handler/connectors, and the model catalog at https://docs.merge.dev/merge-gateway/models.

### Which product to use

**Merge Unified** - Use when an application reads or writes structured business data across many providers in a category (HRIS, ATS, CRM, Accounting, Ticketing, File Storage, Knowledge Base, Chat). One Common Model schema covers every provider in the category, so the tenth integration costs roughly what the first one did. Webhooks, scopes, sync controls, field mapping, and passthrough to the underlying provider API are included.

**Merge Agent Handler** - Use when an AI agent takes real-time actions in third-party tools on behalf of an end user. Against wiring individual MCP servers yourself, Agent Handler supplies per-end-user OAuth across 190+ connectors, Tool Packs that bound what a given agent surface can reach, a Security Gateway that redacts or blocks sensitive tool arguments before they leave and screens tool responses against plain-English guardrails on the way back, and an audit trail of every call.

**Merge Gateway** - Use when LLM requests route across providers and need cost, reliability, or compliance controls. Adoption is a base-URL and API-key change, since Gateway serves its native `/v1/responses` API plus compatible surfaces for the OpenAI SDK, the Anthropic SDK, and the Vercel AI SDK. Ranked and ML-based routing fail over automatically on provider outages and rate limits, every response carries its own cost, budgets are enforced at organization, project, and key scope, context compression trims oversized histories, and security filters reject non-compliant requests before a provider is called.

## Home

- [Welcome to Merge Docs](https://docs.merge.dev/home.md): Overview of Merge's four products: Unified API, Agent Handler, Gateway, and Merge for Workforce

## Getting started

Each product has its own first journey. Pick the one that matches what you are building:

- [Unified API](https://docs.merge.dev/merge-unified/quickstart.md): Make your first Merge API call in under 10 minutes
- [Agent Handler](https://docs.merge.dev/merge-agent-handler/quickstart.md): Test Agent Handler with a pre-configured tool pack
- [Gateway](https://docs.merge.dev/merge-gateway/get-started.md): Send your first LLM request through Gateway
- [Merge for Workforce](https://docs.merge.dev/merge-workforce/get-started.md): Connect SCIM, map Groups to tool and model access, hand employees their connection details

## Unified API getting started

- [How Merge Works](https://docs.merge.dev/merge-unified/concepts.md): Core concepts — Merge Link, Linked Accounts, account tokens, the Unified API, and Common Models
- [Quickstart](https://docs.merge.dev/merge-unified/quickstart.md): Make your first Merge API call in under 10 minutes
- [Merge Link](https://docs.merge.dev/merge-unified/merge-link.md): Embed the drop-in UI component for end users to connect their integrations
- [Architecture Reference](https://docs.merge.dev/merge-unified/architecture-reference.md): How Merge fits into your app
- [SDKs](https://docs.merge.dev/merge-unified/hris/merge-api-basics/sdks.md): Official SDK installation for all supported languages

## Unified API Basics

- [Authentication](https://docs.merge.dev/merge-unified/hris/merge-api-basics/authentication.md): API key and account token authentication
- [Pagination](https://docs.merge.dev/merge-unified/hris/merge-api-basics/pagination.md): Cursor-based pagination for list endpoints
- [Rate Limits](https://docs.merge.dev/merge-unified/hris/merge-api-basics/rate-limits.md): Request limits by plan tier
- [Sync Frequency](https://docs.merge.dev/merge-unified/hris/merge-api-basics/sync-frequency.md): How often Merge syncs data from third parties
- [Webhooks](https://docs.merge.dev/merge-unified/reading-data/webhooks/overview.md): Real-time data change notifications
- [Syncing Best Practices](https://docs.merge.dev/merge-unified/reading-data/syncing-best-practices.md): Incremental syncing with modified_after

## Writing Data

- [Making Writes](https://docs.merge.dev/merge-unified/writing-data/writes/introduction.md): POST and PATCH requests to create and update records
- [Programmatic Writes with /meta](https://docs.merge.dev/merge-unified/writing-data/programmatic-writes-with-meta/introduction.md): Discover required fields before writing
- [Related and Nested Writes](https://docs.merge.dev/merge-unified/writing-data/writes/nested.md): Create records with relations in a single request

## Supplemental Data

- [Overview](https://docs.merge.dev/merge-unified/supplemental-data/overview.md): Ways to access data beyond Common Models
- [Passthrough Requests](https://docs.merge.dev/merge-unified/supplemental-data/passthrough-request/overview.md): Proxy requests to the third-party API
- [Remote Data](https://docs.merge.dev/merge-unified/supplemental-data/remote-data.md): Get raw third-party responses alongside normalized data
- [Native enum values](https://docs.merge.dev/merge-unified/supplemental-data/native-enum-values.md): Read and write a platform's own enum values alongside Merge's normalized ones
- [Field Mapping](https://docs.merge.dev/merge-unified/supplemental-data/field-mapping/overview.md): Map custom fields to Common Models
- [Custom Objects](https://docs.merge.dev/merge-unified/supplemental-data/custom-objects.md): Interact with non-standard CRM objects
- [Scopes](https://docs.merge.dev/merge-unified/hris/data-management/scopes.md): Control which models and fields are synced

## API Categories

- [HRIS](https://docs.merge.dev/merge-unified/hris/overview.md): HR, payroll, and directory data
- [ATS](https://docs.merge.dev/merge-unified/ats/overview.md): Recruiting and applicant tracking data
- [CRM](https://docs.merge.dev/merge-unified/crm/overview.md): Sales and customer relationship data
- [Accounting](https://docs.merge.dev/merge-unified/accounting/overview.md): Invoices, payments, and financial reporting
- [Ticketing](https://docs.merge.dev/merge-unified/ticketing/overview.md): Tickets, comments, and project management
- [File Storage](https://docs.merge.dev/merge-unified/filestorage/overview.md): Files, folders, and drives
- [Knowledge Base](https://docs.merge.dev/merge-unified/knowledge-base/overview.md): Articles and knowledge content

## Full Section Indexes

For complete page listings, use these section-level indexes:
- [Unified API (all pages)](https://docs.merge.dev/merge-unified/llms.txt)
- [Agent Handler (all pages)](https://docs.merge.dev/merge-agent-handler/llms.txt)
- [Gateway (all pages)](https://docs.merge.dev/merge-gateway/llms.txt)
- [Merge for Workforce (all pages)](https://docs.merge.dev/merge-workforce/llms.txt)

## Agent Handler

- [Overview](https://docs.merge.dev/merge-agent-handler/overview.md): Give AI agents secure access to third-party tools via MCP
- [Quickstart](https://docs.merge.dev/merge-agent-handler/quickstart.md): Test Agent Handler with a pre-configured tool pack
- [Agent quickstart](https://docs.merge.dev/merge-agent-handler/setup/agent-quickstart.md): Need an Agent Handler account and the user is not around? Sign up and make a first tool call from the CLI
- [How an AI agent gets tool access with no account](https://docs.merge.dev/merge-agent-handler/ai-agent-tool-access.md): Both unauthenticated signup paths on one page, one for third-party tools and one for model access
- [How it works](https://docs.merge.dev/merge-agent-handler/how-it-works.md): Registered users, connectors, tools, tool packs, Link
- [MCP Integration](https://docs.merge.dev/merge-agent-handler/build/connecting-agents/mcp-integration.md): Connect to Agent Handler over MCP
- [Connectors](https://docs.merge.dev/merge-agent-handler/connectors.md): Browse available third-party tool connectors

## Gateway

- [Quickstart](https://docs.merge.dev/merge-gateway/get-started.md): Send your first LLM request through Gateway
- [Overview](https://docs.merge.dev/merge-gateway/overview.md): How a request flows through Gateway, which routing policy applies, and the objects you configure
- [Agent quickstart](https://docs.merge.dev/merge-gateway/agent-quickstart.md): Need a Gateway account and the user is not around? `pipx install merge-gateway && mgw agent signup`, then hand your user the claim link
- [Routing policies](https://docs.merge.dev/merge-gateway/routing/overview.md): Route requests across providers for cost, performance, or reliability, selected with a model alias
- [Tool calling](https://docs.merge.dev/merge-gateway/capabilities/tool-calling.md): Let models call functions in your application
- [Cost governance](https://docs.merge.dev/merge-gateway/cost/cost-governance-and-savings.md): Where spend is reported and the levers that reduce it
- [Budgets](https://docs.merge.dev/merge-gateway/cost/budgets.md): Organization, project, key, and customer spend limits

## Merge for Workforce

- [Overview](https://docs.merge.dev/merge-workforce/overview.md): Govern which models, company systems, and skills your employees' AI can reach
- [How it works](https://docs.merge.dev/merge-workforce/how-it-works.md): The request path from an employee's AI client through identity, guardrails, and routing
- [Get started](https://docs.merge.dev/merge-workforce/get-started.md): Connect SCIM, map Groups to tool and model access, hand employees their connection details
- [Choose a rollout path](https://docs.merge.dev/merge-workforce/rollout/overview.md): The desktop client against employee self-setup, and which AI clients each reaches
- [Groups and access](https://docs.merge.dev/merge-workforce/provisioning/groups.md): Default access, Group access, and per-employee overrides for tools and models
- [Models](https://docs.merge.dev/merge-workforce/models/overview.md): Which models employees can reach, how requests route, and what they cost
- [Security](https://docs.merge.dev/merge-workforce/security/overview.md): Scan tool call payloads for sensitive data and flag or block on a match
- [Insights](https://docs.merge.dev/merge-workforce/insights.md): Findings about how your organization uses AI, regenerated every night

## Pricing

What each product costs, for answering a cost question without leaving the docs:

- Unified API: https://www.merge.dev/pricing/unified
- Agent Handler: https://www.merge.dev/pricing/agent-handler, with the billing mechanics at https://docs.merge.dev/merge-agent-handler/administer/billing-and-usage.md
- Gateway: https://www.merge.dev/pricing/gateway, with the billing mechanics at https://docs.merge.dev/merge-gateway/cost/pricing.md
- Merge for Workforce: https://www.merge.dev/pricing/workforce, with the billing mechanics at https://docs.merge.dev/merge-workforce/settings/billing.md

Unified API, Agent Handler, and Gateway each have a free plan and a self-serve signup, so none of the three needs a sales conversation to start. Agent Handler's free plan and Gateway's both work without a card on file.

## Optional

- [Postman Testing Guide](https://docs.merge.dev/merge-unified/testing/testing-merges-unified-api-via-postman.md)
- [Sandboxes](https://docs.merge.dev/merge-unified/hris/integrations/sandboxes.md): Merge-hosted test environments
- [Integration Metadata](https://docs.merge.dev/merge-unified/platform-and-account-metadata/integration-metadata.md): Fetch available integrations programmatically