Graph Indexer for Junie

Graph Indexer for Junie is a local MCP server that gives JetBrains Junie exact references, call graphs and change impact for your project. Run npx graph-indexer init and it writes a graph-indexer entry to .junie/mcp/mcp.json and a short instructions block to AGENTS.md.

How do I add Graph Indexer to Junie?

From the repository root, with Node.js 22.5 or later:

npx graph-indexer init

init configures Junie when it finds a .junie folder. If you have none yet, force it with npx graph-indexer init --agents junie, or configure every supported agent with --all. Without any detected agent, init falls back to Claude Code only.

What does npx graph-indexer init change for Junie?

For Junie, init touches these files:

Use --dry-run to preview. If .junie/mcp/mcp.json contains comments or is not plain JSON, init leaves it alone and prints the entry for you to add.

What does the manual Junie configuration look like?

The entry init writes to .junie/mcp/mcp.json is the standard stdio form:

{
  "mcpServers": {
    "graph-indexer": {
      "command": "npx",
      "args": ["-y", "graph-indexer@3", "serve"]
    }
  }
}

There is no --repo argument: Graph Indexer indexes the git repository of the directory it starts in. If you need another path, add "--repo", "/path/to/repo" to args, or set GRAPH_INDEXER_REPO.

What does Junie gain from Graph Indexer?

Junie’s agent gets eight read-only tools over stdio, each reply typically 400 to 1,500 tokens:

• find_references lists every real use of a symbol, bound through scopes, imports and receiver types, and says whether the list is complete.
• call_graph shows callers and callees across files with confidence per edge.
• change_impact returns dependents by distance, the tests to run and a risk level.
• check_changes flags syntax errors, calls that no longer fit and removed names still in use, without a build.

Against the TypeScript compiler on 400 nestjs symbols, find_references reached 99.7% precision and 96.2% recall; grep reached 12.8% precision (benchmarks). The index covers 16 tree-sitter grammars (languages). Graph Indexer is not a type checker: generics, reflection and any are only partly visible.

Graph Indexer itself makes no network calls and sends no telemetry; Junie still sends what it reads to its model provider. See the tools reference and the other agents.