Release Of Kurlo 3.1 Open API Client

Published release of Kurlo 3.1, a graphical interface for debugging and testing APIs, developed as an alternative to Postman, Insomnia, Bruno and Yaak. The code is written in Go and Svelte using the Wails framework, which uses the system WebView instead of the built-in Chromium engine, and distributed under a license MIT. Ready-made assemblies are generated for Linux (AppImage), Windows and macOS.

Main features

• Requests HTTP, GraphQL, gRPC, WebSocket, Socket.IO, SSE and MCP.
• Collections are stored in the form YAML files that can be kept in a Git repository along with the API code. There is a built-in interface for working with Git.
• Import from Postman, Insomnia, Bruno, OpenAPI and HAR. Postman scripts (pm.test, pm.expect, pm.sendRequest) are transferred as is.
• There is emulation of browser checks: CORS preflight request and CSP connect-src restrictions are checked against the Fetch and CSP3 specifications. This allows you to see in the client the error that the browser will receive even before the release.
• Local mock server, console utility for launching collections in continuous integration systems and MCP server.
• Optional AI agent that works with the model selected by the user (OpenRouter, Ollama, LM Studio, its own API key) or through Claude Code and Codex. Changes are applied only after confirmation by the user; passwords and model keys are not transferred.
• No account linking, paid functions or telemetry collection.
• Ability to work without access to the Internet, including in closed circuits; for the AI ​​agent, you can use a local model through Ollama or LM Studio.

Changes in version 3.1

• Synchronize the collection with the OpenAPI specification, downloaded from a URL or from a file in the repository. For CI, the “kurlo openapi check” command has been added, displaying added, modified and deleted operations.
• Variables set at the level of an individual request (vars).
• JWT Bearer authorization: the token is signed on each send, HS, RS, PS and ES algorithms are supported.
• Response checks (status code, time, headers, JSON fields) without writing scripts (assertions).
• Cancel deletion and list recently deleted items (Undo).
• Color marking of environments (so that the request is not accidentally sent to the production server) and reordering requests in drag-n-drop mode.
• Speed up opening, saving and scrolling of workspaces with thousands of requests and examples on all OSes.