Explore, analyze, and decompile Java JAR files via MCP
Explore, analyze, and decompile Java JAR files via MCP. The dejared mcp server wraps that behind the Model Context Protocol, so an assistant can use it through 14 defined tools rather than through you.
A Model Context Protocol (MCP) server for exploring, analyzing, and decompiling Java JAR files. Designed for AI-powered development tools, dejared-mcp connects your IDE or CLI assistant to inspect package structures, search bytecode, and decompile classes using CFR, Vineflower, or Procyon.
dejared-mcp is a Java-based MCP server distributed as an npm package. It provides nine tools organized into three categories: discovery, hunting, and deep analysis. AI assistants use these tools to navigate JAR file structures, search for classes and string literals in bytecode, and decompile .class files back to readable Java source code.
Everything the assistant can do here goes through one of these:
macOS — ~/Library/Application Support/Claude/claude_desktop_config.jsonWindows — %APPDATA%\Claude\claude_desktop_config.jsonCommand — npx -y dejared-mcpName — dejaredTransport — StdioArguments — -y dejared-mcpLinux — $XDG_CACHE_HOME/dejared-mcp (defaults to ~/.cache/dejared-mcp)dejared_list_packages — List all packages with class countsdejared_list_classes — List classes in a specific packagedejared_list_resources — List non-class resource filesdejared_read_resource — Read text resources (YAML, XML, properties, JSON, and others)dejared_search_class — Search classes by namedejared-mcp on npm is all you need. Most clients run it directly, so configuration is a few lines and a restart.
You will need one environment variable: DEJARED_JAVA_PATH. Keep credentials in your client's env block or a secrets manager rather than in a file you might commit.
This sits in the database access group, where several servers overlap in what they claim to do but differ sharply once you actually set them up. Dejared's toolset — macOS, Windows, Command and 11 more — is a fair guide to whether it matches your workflow. It is maintained by HuynhKhanh1402; worth a glance at recent repository activity before you build anything load-bearing on it.
We check each listing at SyncDev against the project's documentation before it goes live — if something here drifts out of date, it is a bug worth reporting.
| Tool | What it does |
|---|---|
| macOS | ~/Library/Application Support/Claude/claude_desktop_config.json |
| Windows | %APPDATA%\Claude\claude_desktop_config.json |
| Command | npx -y dejared-mcp |
| Name | dejared |
| Transport | Stdio |
| Arguments | -y dejared-mcp |
| Linux | $XDG_CACHE_HOME/dejared-mcp (defaults to ~/.cache/dejared-mcp) |
| dejared_list_packages | List all packages with class counts |
| dejared_list_classes | List classes in a specific package |
| dejared_list_resources | List non-class resource files |
| dejared_read_resource | Read text resources (YAML, XML, properties, JSON, and others) |
| dejared_search_class | Search classes by name |
| dejared_search_string | Search string literals in bytecode (URLs, SQL, error messages) |
| dejared_get_metadata | Extract class metadata via ASM (fast, no decompilation) |
{
"mcpServers": {
"dejared": {
"command": "npx",
"args": ["-y", "dejared-mcp"]
}
}
}Configuration as documented by the project. Restart the client after saving.
| Variable | Description | Required |
|---|---|---|
| DEJARED_JAVA_PATH | Filesystem location the server is allowed to use. | Optional |
Read-only SQL access to Postgres — let your assistant inspect schemas and answer questions from real data.
Manage your whole Supabase project in conversation — database, auth, storage, Edge Functions and branches.
Query, modify and analyse local SQLite databases in conversation — the fastest way to chat with a data file.
Metabase ships its own MCP endpoint — search your BI content, build and run queries, and save questions and dashboards without leaving the chat.
Official MongoDB server covering data, schemas and Atlas management — from find queries to spinning up clusters.
Serverless Postgres with database branching — point your assistant at Neon and let it work on disposable copies.