mockd MCP Server

<h3 align="center">One binary. Seven protocols. Zero dependencies.</h3>

Mock HTTP, gRPC, GraphQL, WebSocket, MQTT, SSE, and SOAP from a single CLI tool. Import OpenAPI specs. Build digital twins. Let AI agents create mocks for you.

Website · Docs · Samples · Contributing

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Quick Start

# Install
curl -sSL https://get.mockd.io | sh

# Start + create a stateful CRUD API in one command
mockd start
mockd add http --path /api/users --stateful users

# It works immediately
curl -X POST localhost:4280/api/users -d '{"name":"Alice","email":"[email protected]"}'
# → {"id":"a1b2c3","name":"Alice","email":"[email protected]"}

curl localhost:4280/api/users
# → {"data":[{"id":"a1b2c3","name":"Alice","email":"[email protected]"}],"meta":{"total":1}}

<details> <summary><strong>More install options</strong></summary>

brew install getmockd/tap/mockd                                          # Homebrew
docker run -p 4280:4280 -p 4290:4290 ghcr.io/getmockd/mockd:latest      # Docker
go install github.com/getmockd/mockd/cmd/mockd@latest                    # Go

Pre-built binaries for Linux, macOS, and Windows on the Releases page.

</details>

Why mockd?

Every other mock tool makes you choose: pick one protocol, install a runtime, bolt on extensions. mockd doesn't.

	mockd	WireMock	Mockoon	json-server	Prism	MockServer
Single binary, no runtime	:white_check_mark:	:x: JVM	:x: Node	:x: Node	:x: Node	:x: JVM
HTTP + gRPC + GraphQL + WS	:white_check_mark:	🔌 Ext	:x:	:x:	:x:	Partial
MQTT + SSE + SOAP + OAuth	:white_check_mark:	:x:	:x:	:x:	:x:	:x:
Stateful CRUD	:white_check_mark:	:x:	:white_check_mark:	:white_check_mark:	:x:	:x:
Import OpenAPI/Postman/HAR	:white_check_mark:	:white_check_mark:	:white_check_mark:	:x:	:white_check_mark:	:white_check_mark:
Chaos engineering	:white_check_mark:	:white_check_mark:	:x:	:x:	:x:	:x:
MCP server (AI-native)	:white_check_mark:	:x:	:x:	:x:	:x:	:x:
Cloud tunnel sharing	:white_check_mark:	:x:	:white_check_mark:	:x:	:x:	:x:
Built-in web dashboard	:white_check_mark:	:x:	:white_check_mark:	:x:	:x:	:x:

🔌 Ext = available via separate extension, not bundled. mockd includes everything in a single binary.

Digital Twins

Import a real API spec, bind it to stateful tables, and get a mock that passes the real SDK:

# mockd.yaml — Stripe digital twin
version: "1.0"
imports:
  - path: stripe-openapi.yaml
    as: stripe
tables:
  - name: customers
    idStrategy: prefix
    idPrefix: "cus_"
    seedData:
      - { id: "cus_1", name: "Acme Corp", email: "[email protected]" }
extend:
  - { mock: stripe.GetCustomers, table: customers, action: list }
  - { mock: stripe.PostCustomers, table: customers, action: create }
  - { mock: stripe.GetCustomersCustomer, table: customers, action: get }
  - { mock: stripe.PostCustomersCustomer, table: customers, action: update }
  - { mock: stripe.DeleteCustomersCustomer, table: customers, action: delete }

mockd start -c mockd.yaml --no-auth
curl -X POST localhost:4280/v1/customers -d "name=Test&[email protected]"
# → {"id":"cus_a1b2c3","object":"customer","name":"Test","email":"[email protected]"}

Validated with real SDKs:

• Stripe: 49/49 stripe-go SDK tests pass
• Twilio: 13/13 twilio-go SDK tests pass
• OpenAI: openai Python SDK verified (models, assistants, chat completions)

See mockd-samples for complete digital twin configs.

AI-Native (MCP)

mockd includes a built-in Model Context Protocol server