LabscoMCP early access ↗
IcyHot09MCP SERVER

OpenGrok

Search a huge indexed codebase through OpenGrok from your assistant — definitions, references, blame, include graphs and diffs, with compound tools that collapse four calls into one.

by IcyHot09 ↗Code Intelligence & Repository IndexingCommunity

LABSCO SUMMARY

The compound tools are the reason to use it.

Asking "what is this symbol" naively costs four round trips and a great deal of context; the symbol-context tool does the same work in one, and the project puts the saving at roughly 92% fewer tokens. On a codebase where the index is stale, check index health before you trust an empty result — that is the failure mode that otherwise looks like the code not existing.

What it is

A bridge between an existing OpenGrok index and an MCP client. Instead of the model grepping a checkout it does not have, it queries the index your organization already runs — which is what makes this workable on codebases too large to clone, let alone read.

What you get

  • Search and read — opengrok_search_code for full-text, definitions, references, path and history with file_type filtering, opengrok_find_file, opengrok_get_file_content (large files need start_line and end_line), opengrok_browse_directory, opengrok_list_projects, opengrok_search_suggest
  • History — opengrok_get_file_history for commit logs, opengrok_get_file_annotate and opengrok_blame for line-by-line authorship, opengrok_get_file_diff for a unified diff with surrounding context
  • Compound tools that merge several round trips: opengrok_get_symbol_context finds the definition, reads the source, fetches headers and gets references in one call; opengrok_search_and_read searches then immediately reads the context; opengrok_batch_search runs 2-5 queries and deduplicates hits across them
  • Investigation tools — opengrok_what_changed groups recent line changes by commit with author, date and SHA; opengrok_dependency_map walks #include and import chains up to depth 3 as a directed graph; opengrok_search_pattern for regex; opengrok_call_graph for call-chain tracing
  • opengrok_index_health — latency, backend connectivity, staleness score and latency trend, for when results look wrong
  • A memory bank that survives across turns: opengrok_memory_status, opengrok_read_memory and opengrok_update_memory over active-task.md and an append-only investigation-log.md
  • Code Mode, enabled with OPENGROK_CODE_MODE=true, which replaces the catalog with a small interface — opengrok_api for the spec and opengrok_execute to run JavaScript in a sandboxed QuickJS VM against env.opengrok.*

Requirements

A reachable OpenGrok server: OPENGROK_BASE_URL is the one required setting, with OPENGROK_USERNAME and OPENGROK_PASSWORD only if your instance is not anonymous. The easiest install is the VS Code extension, which ships the server pre-packaged and configures itself. Otherwise npm install -g opengrok-mcp-server then opengrok-mcp setup — an interactive wizard that collects the URL and credentials and registers the server with your client, storing the password in the OS keychain (macOS Keychain, Windows Credential Manager, Linux libsecret) with an encrypted file fallback for headless machines. Set OPENGROK_VERIFY_SSL to false only for internal CA certificates. Package opengrok-mcp-server at 9.2.14.

Setup effort

One command — npm install -g opengrok-mcp-server

See installation options