Ariadne

What the MikhailHal/ariadne MCP server does

The MikhailHal/ariadne MCP server exposes affected-test selection for Kotlin and Android repositories through MCP. Its main purpose is to reduce the tests an agent runs after modifying code. The result is a sorted list of affected test fully qualified names rather than a test command or test report.

The analyzer covers function-level relationships, including calls involving functions, properties, property initializers, delegates, accessors, constructors, and callable references. It can discover modules from Gradle settings and identify source sets across Android variants. The project description reports validation against Now in Android, including 34 modules and an approximately four-second end-to-end query time in that project.

How it works

An MCP client sends a project path to the get_affected_tests tool. The MikhailHal/ariadne MCP server runs Git diff itself, then passes the changed Kotlin code to sazanami for static analysis. Sazanami builds a call graph and finds tests reachable from the changed code.

The scope option controls which changes are considered. deep, the default, compares changes since a base branch and includes committed and uncommitted work. shallow compares only uncommitted changes against HEAD; in that mode, base_branch is ignored. For deep analysis, the server uses the repository's default branch from origin/HEAD when no branch is supplied. If that reference is unavailable, the request returns an error asking for an explicit base branch.

Setup and configuration

Install the executable with Homebrew:

brew install mikhailhal/tap/ariadne

Register the ariadne executable with an MCP client. The README gives Claude Code and Claude Desktop configurations, including a stdio entry whose command is ariadne. Docker is also supported by mounting the project at /workspace and passing that path as project_path. A release fat JAR can run with JDK 21 or newer, and the repository can be built with Gradle's shadowJar task.

Tools and capabilities

The server provides one documented tool:

• get_affected_tests: accepts required project_path, optional scope (deep or shallow), and optional base_branch for deep scope.

Responses contain sorted affected test names. If changes occur in build scripts, resources, or source sets outside the analysis scope, the response adds a recommendation to run the full test suite. Analysis has a 120-second timeout and returns an explicit error if that limit is reached.

Limitations and notes

The MikhailHal/ariadne MCP server uses static call-graph analysis, so it cannot reliably connect dependencies hidden behind reflection, dependency-injection containers, or framework-dispatched callbacks. Examples include lifecycle callbacks, lint detector methods, and application startup methods when the test does not call them directly. Flux/MVI dispatch-to-collection relationships may also be missed.

Changes to build scripts, resources, or unscanned source sets are reported rather than treated as having no affected tests. The tool is intended to narrow tests during development, not replace a full or conservative CI test run before merging.