Tavern

Free plan LinuxSelf-hosted

What Tavern is

Tavern is a free tool for developers who want to automate API tests with YAML. It can be used as a pytest plugin, through the tavern-ci command-line interface, or as a Python library; the documentation recommends running it with pytest. A test file names the test and lays out one or more stages with requests and expected responses. Checks can cover status codes, JSON bodies, headers, and redirect query parameters.

Tavern supports RESTful APIs, MQTT-based APIs, gRPC services, and GraphQL. Tests can load variables from configuration files, reuse values saved in earlier stages, and read environment variables for credentials such as passwords or bearer tokens. Its documented default backends use requests for HTTP, paho-mqtt for MQTT, grpcio for gRPC, and gql for GraphQL. A plugin system can alter how requests are made, with documented plugins for Flask and FastAPI/Starlette test clients. Tavern has no GUI, API monitoring, or mock servers.

Who it suits

Tavern suits developers who want to automate API checks in YAML and run them with pytest, a command-line tool, or a Python integration. It covers REST, MQTT, gRPC, and GraphQL testing.

What it does well

Free plan and free, open-source tool
Supports REST, MQTT, gRPC, and GraphQL
Checks status codes, JSON, headers, and redirects
Reuses configuration, response, and environment values
Can integrate with test frameworks and CI setups

What to know first

No graphical interface
Does not provide API monitoring
Does not provide mock servers

Limits

Tavern is free plan. It does not include a GUI, API monitoring, or mock-server capability.

Plans

Plan	Billed and limits	Price
Tavern	Free and open-source API test automation tool	Free

As tavern.readthedocs.io lists them, read 9 Oct 2026. The maker's own page has the final word.

Getting started

Install Tavern in a Linux or self-hosted Python environment
Write a YAML test with a name, stages, requests, and expected responses
Run the tests with pytest, tavern-ci, or Tavern's Python library
Load configuration variables and environment values for credentials
Connect the tests to a test framework or continuous-integration setup

Verdict

Tavern provides YAML-based API testing across several protocols, with reusable test data and multiple ways to run tests. Consider its lack of a GUI, monitoring, and mock servers when deciding whether it fits your workflow.

Questions

How much does Tavern cost?

The Tavern plan is free and listed as free plan. It is described as free and open-source API test automation.

Which APIs can Tavern test?

Tavern supports RESTful APIs, MQTT-based APIs, gRPC services, and GraphQL.

How are Tavern tests written?

Tests are YAML documents containing a test name and one or more stages with requests and expected responses.

Can Tavern run in continuous integration?

Yes. Tavern can run through tavern-ci or its Python library and integrate with test frameworks and continuous-integration setups.

Does Tavern provide a mock server or GUI?

No. Tavern does not provide a GUI, API monitoring, or mock servers.

How are secrets handled in tests?

Tests can read environment variables for credentials such as passwords or bearer tokens, keeping those values out of shipped test code.

Facts from Tavern's own pages

Assertions: Response checks can validate status codes, JSON bodies, headers, and redirect query parameters. · tavern.readthedocs.io, 9 Oct 2026
Audience: The project describes Tavern as a focused tool for developers to automate API tests. · tavern.readthedocs.io, 9 Oct 2026
Backends: The documented default backends use requests for HTTP, paho-mqtt for MQTT, grpcio for gRPC, and gql for GraphQL. · tavern.readthedocs.io, 9 Oct 2026
CI use: The project documentation says Tavern can be integrated into test frameworks or continuous integration setups through its Python library or the tavern-ci command-line tool. · tavern.readthedocs.io, 9 Oct 2026
Community plugin: The plugins page lists tavern-grpc-web as a community-maintained backend for unary gRPC-Web calls over HTTP. · tavern.readthedocs.io, 9 Oct 2026
Development: The changelog lists version 3.6.0, dated 2026-05-31, as the latest release shown. · tavern.readthedocs.io, 9 Oct 2026
Extensibility: Tavern has a plugin system for changing how requests are made, and its documentation names plugins for Flask and FastAPI/Starlette test clients. · tavern.readthedocs.io, 9 Oct 2026
Founded: 2017 · tavern.readthedocs.io, 28 Sept 2026
GraphQL: The plugin documentation lists GraphQL as a built-in request backend. · tavern.readthedocs.io, 9 Oct 2026
How to run: The documentation recommends using Tavern with pytest; it can also be run through the tavern-ci command-line interface or integrated using its Python library. · tavern.readthedocs.io, 9 Oct 2026
Integrations: The documented default backends use requests for HTTP, paho-mqtt for MQTT, grpcio for gRPC, and gql for GraphQL. · tavern.readthedocs.io, 9 Oct 2026
Limitations: Tavern does not have a GUI, API monitoring, or mock servers, according to its comparison with Postman and Insomnia. · tavern.readthedocs.io, 9 Oct 2026
Maintenance: The documentation names @michaelboulton as the current maintainer. · tavern.readthedocs.io, 9 Oct 2026
Notable limits: Tavern has no GUI and does not provide API monitoring or mock servers. · tavern.readthedocs.io, 9 Oct 2026
Project history: The project says Tavern was started in 2017. · tavern.readthedocs.io, 9 Oct 2026
Protocols: Tavern supports testing RESTful APIs, MQTT-based APIs, and gRPC services. · tavern.readthedocs.io, 9 Oct 2026
Purpose: Tavern is a pytest plugin, command-line tool, and Python library for automated API testing using YAML syntax. · tavern.readthedocs.io, 9 Oct 2026
Pytest: The documentation recommends using Tavern with pytest, which can discover and run Tavern YAML test files. · tavern.readthedocs.io, 9 Oct 2026
Response checks: Response checks can include status codes, JSON, headers, and redirect query parameters. · tavern.readthedocs.io, 9 Oct 2026
Reusable data: Tests can save values from responses and reuse them in later requests, and can load variables from configuration files. · tavern.readthedocs.io, 9 Oct 2026
Reusable test data: Tests can use variables from configuration files or earlier stages, and can read environment variables for values such as passwords or bearer tokens. · tavern.readthedocs.io, 9 Oct 2026
Secrets: The documentation shows environment variables being used for credentials such as passwords or bearer tokens that should not be shipped with test code. · tavern.readthedocs.io, 9 Oct 2026
Security-related capability: The documentation shows using environment variables to keep passwords or bearer tokens out of test code shipped with the tests. · tavern.readthedocs.io, 9 Oct 2026
Supported APIs: Tavern supports testing RESTful APIs, MQTT-based APIs, and gRPC services. · tavern.readthedocs.io, 9 Oct 2026

Where Tavern stands on Freedom251

API Testing Tools#30 of 34