Best API Clients for GitLab

Postman serves as a collaborative platform for developing APIs, designed to simplify the entire process of API creation and enhance teamwork, enabling the rapid development of superior APIs. The platform's features facilitate each phase of API construction, making it easier to collaborate and accelerate the creation of high-quality APIs. Users can quickly and effortlessly send requests for REST, SOAP, and GraphQL directly within Postman, optimizing their workflow. Additionally, it allows for the automation of manual tests, seamlessly integrating them into your CI/CD pipeline to safeguard against potential issues when code changes are deployed to production. API behavior can be communicated effectively by simulating endpoints and their respective responses without the need for a backend server setup. You can also generate and publish visually appealing, machine-readable documentation, which helps in making your API more accessible for users. Regular performance and response time checks ensure you stay informed about your API's health, allowing for proactive management. Lastly, Postman fosters a shared environment for API creation and consumption, enabling real-time collaboration among team members. Postman’s AI Agent Builder revolutionizes the development of AI agents with its no-code platform, enabling users to build, test, and deploy powerful agents without coding expertise. It provides access to a vast library of over 100,000 APIs and a variety of LLMs, offering tools to compare their performance, cost, and response quality. The visual workflow builder simplifies creating multi-step agent interactions, and its testing tools ensure reliability before deployment.

Bruno is a developer-first, open-source API client that’s redefining what an API tool should be. Built from the ground up for speed, privacy, and simplicity, Bruno offers everything developers need to explore, test, and document APIs without the cloud lock-in, telemetry, or bloat that’s become standard elsewhere. Instead of chasing “platform” status, Bruno focuses on doing one thing exceptionally well: being a pure API client. It’s completely local... all your requests, environments, and collections stay on your machine. Nothing is uploaded or tracked. The result is a faster, safer, and more transparent workflow that developers actually enjoy using. Bruno is also Git-native, meaning collections live in plain text and can be versioned, diffed, and reviewed just like code. Branching, merging, and pull requests all just work — no proprietary formats or walled gardens. For teams that already use GitHub, GitLab, or Bitbucket, Bruno slots right in with zero friction. Under the hood, Bruno supports Postman and Swagger imports, test scripting in JavaScript, a powerful CLI, VS Code extension, and CI/CD integration for automated API testing. Since its launch in 2022, Bruno has seen explosive community growth: over 2.5 million downloads, 150,000+ daily users, and 37,000+ GitHub stars. Trusted by engineers at Microsoft, Capital One, GitHub, and FedEx, Bruno is proving that developer tools don’t need a cloud backend to scale , they just need to respect how developers actually work. In short: Bruno is what the API client should have been all along ... local, fast, Git-based, and open-source.

Craft, troubleshoot, and evaluate APIs with a human touch rather than a mechanical approach. At last, a workflow that you'll genuinely appreciate. Introducing the Collaborative API Design Tool, which provides a platform for creating, validating, and overseeing OpenAPI specifications. This Desktop API client facilitates interactions with both REST and GraphQL. You can make requests and analyze responses seamlessly. Effortlessly create and organize your requests, set up environment variables, manage authentication, produce code snippets, and much more. Dive deep into response details—explore the entire request timeline, including status codes, body, headers, cookies, and additional information. Organize your project with workspaces, folders, and environments, utilizing a drag-and-drop interface for requests, along with straightforward data import and export options. Within a single collaborative API design editor, you can create, modify, lint, troubleshoot, preview, and manage your OpenAPI specifications. Additionally, generate configurations for popular API gateways such as the Kong API Gateway and Kong for Kubernetes. Synchronize your API designs with version control systems like GitHub or GitLab, and deploy directly to API gateways such as Kong with just a click, streamlining your development process significantly. This tool not only enhances productivity but also fosters collaboration among teams in designing robust APIs.

RapidAPI for Mac is a full-featured API development tool that provides developers with everything they need to test, document, and manage APIs efficiently. Built exclusively for macOS, it offers a visually rich HTTP client that allows users to send requests, analyze responses, and refine APIs in real time. The platform supports API description standards such as JSON Schema, Swagger, RAML, and API Blueprint, making it easy to create and maintain structured API documentation. Developers can visually define parameters, constraints, and request details, improving clarity and accuracy. With built-in code generation and export capabilities, it simplifies sharing and integrating APIs across different environments. RapidAPI for Teams enhances collaboration by enabling synchronized projects, real-time updates, and version control-like workflows. Teams can work on separate branches and merge changes seamlessly, ensuring smooth collaboration. The tool combines testing, documentation, and teamwork into one unified platform. It is ideal for developers looking to accelerate API development and maintain consistency across projects.