Scalex plugin
A plugin gives agents Scala 2, Scala 3 and Java code navigation by AST: definitions, references and types with no build or server.
- 110 ★ on the repository
- Last commit
- MIT
Extended access
Why this level
- On first run the script downloads a native binary from GitHub and verifies its SHA-256, but it runs with your privileges
- The tool reads repository sources and writes a cache next to the project
Install
- Works in
In your terminal, with SkillFoxx CLI
npx skillfoxx add plugins/scalexDetects the agents on your machine, shows the access level and pins the version.
Other ways to install
Access and checks
How we reviewExtended accessThe tool runs code or makes network calls and only reads external data.
- On first run the script downloads a native binary from GitHub and verifies its SHA-256, but it runs with your privileges
- The tool reads repository sources and writes a cache next to the project
This is third-party code. Review the repository files before installing.
What it does
Scalex parses Scala and Java sources from Git directly by syntax tree and answers questions about code without compiling or a build server. An agent finds definitions and implementations, reads a method body, walks type hierarchies, packages and annotations and sees which declarations changed relative to `main`. The `explain` command collects a type's definition, documentation, members and implementations in one answer. Output comes as JSON with limits and batch queries to keep context small. The plugin contains a skill and a bootstrap script that downloads a native binary on first run and verifies its SHA-256.
Who it is for. Scala developers and teams exploring an unfamiliar repository with Claude Code or Codex who do not want to wait for a build import in Metals or an IDE.
Good fit when
- An unfamiliar Scala project must be understood in an evening without setting up the build
- You need to find where `UserService` is defined and what implements it
- Before editing a method, its body and the tests that reference it are read
- A branch is checked for declarations changed relative to `main`
- The repository is opened in CI or on a server with no JVM or build
Not a fit when
- You need exact compiler-resolved references: Scalex finds candidates by name
- You work on Windows: macOS Apple Silicon, macOS Intel and Linux x64 are supported
- The code is not in Git: the tool indexes only tracked files
Example request
Use Scalex to explain how a request moves through this project: show the main types and the files to read next.Limitations
References are found as name-based candidates, and types are not resolved by a compiler. Platforms are macOS Apple Silicon, macOS Intel and Linux x64. On first run the script downloads a binary from GitHub releases and verifies its checksum, so the first run fails offline. The plugin adds no `scalex` command to PATH and calls its own `scripts/scalex-cli`. Publishing a release does not update an installed bootstrap, so update the plugin by command. The cache is kept per repository. The last commit is from 18 September 2026.
How to disable. In Claude Code run `claude plugin uninstall scalex@scalex-marketplace` and remove the plugin in Codex through `codex plugin`. Delete the repository cache directory and downloaded binaries by hand.
FAQ
Do I need a JVM or a build server?
No. The native binary parses sources itself, with no compilation, no JVM and no background daemon.
Which command should I start with?
Start with `scalex overview --concise`, then `scalex search Service --kind trait --limit 10` and `scalex explain UserService --brief` for the needed type.
How do I install the skill in another agent?
Clone the repository and copy `plugins/scalex/skills/scalex` into the agent's skills directory, then reload its skills.
How do I update the plugin?
Run `claude plugin marketplace update scalex-marketplace` and `claude plugin update scalex@scalex-marketplace`; Codex has paired `codex plugin` commands.
Which platforms does it run on?
On macOS with Apple Silicon, macOS with Intel and Linux x64. Git is required, a JVM is not.
Discussion
No questions or reviews yet.
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README in short
The project motto: grep knows text, Scalex knows Scala. It neither compiles nor keeps processes, so output is fast, but references remain candidates.