OpenGrok MCP Server

Name: OpenGrok MCP Server
Author: IcyHot09

by IcyHot09version 9.6.0i★ –iRuns on your computer

Registry nameio.github.IcyHot09/opengrok-mcp-server

Install

Overview

Description from the maker (original English)

MCP server bridging OpenGrok search engine with AI for instant context across massive codebases.

PopNx MCP’s three pillars

These three are never merged into one score: opinions, measurements and popularity are different things.

User voiceiNo reviews yetReviews open together with accounts in a later step
Our basic checksi1 of 1 passedChecked from public information; code not scanned yet
UsageiVery new↓ 132/wk · ★ –

What you can do with it

We have not written a plain-language summary for this one yet. Below are the facts we read from the registry.

Connection: Runs on your computer
Transport: stdio
Category: Search & AI memory
You need to fill in: OPENGROK_BASE_URL, OPENGROK_PASSWORD

Install

Pick the AI app you use, then copy the settings.

Before you install

Basic checks: 1 of 1 passed
Runs on your computer with your user’s permissions (files, network, apps).
You fill in yourself: OPENGROK_BASE_URL, OPENGROK_USERNAME, OPENGROK_PASSWORD, OPENGROK_VERIFY_SSL, OPENGROK_CODE_MODE, OPENGROK_ENABLE_MEMORY_TOOLS, OPENGROK_DEFAULT_PROJECT, OPENGROK_CONTEXT_BUDGET, OPENGROK_API_VERSION, HTTP_PROXY, OPENGROK_RESPONSE_FORMAT_OVERRIDE, OPENGROK_MEMORY_BANK_DIR, OPENGROK_LOCAL_COMPILE_DB_PATHS, OPENGROK_ENABLE_ELICITATION, OPENGROK_ENABLE_SAMPLING, OPENGROK_SAMPLING_MODEL, OPENGROK_ENABLE_FILES_API, OPENGROK_ENABLE_OBSERVATION_MASKER, OPENGROK_OBSERVATION_MASKER_TURNS, OPENGROK_SAMPLING_MAX_TOKENS, OPENGROK_AUDIT_LOG_FILE, OPENGROK_RATELIMIT_RPM, OPENGROK_PER_TOOL_RATELIMIT, OPENGROK_TIMEOUT, OPENGROK_DEFAULT_MAX_RESULTS, OPENGROK_PASSWORD_FILE, OPENGROK_MAX_RESPONSE_BYTES, OPENGROK_SEARCH_AND_READ_CAP, OPENGROK_STRICT_SSRF, OPENGROK_JWT_ISSUER, OPENGROK_GRAMMAR_DIR

Values marked secret are keys to your account. Never share them or paste them into a chat.

You need

npmNode.js installed (for the npx command)

Which app do you use?

ClaudeClaude CodeCursorVS CodeChatGPT

Pick your app above. We remember it, so next time the button says “Install in …”.

Open Claude Desktop → Settings → Developer → Edit Config, and paste this into claude_desktop_config.json

{
  "mcpServers": {
    "opengrok": {
      "command": "npx",
      "args": [
        "-y",
        "opengrok-mcp-server"
      ],
      "env": {
        "OPENGROK_BASE_URL": "your-value",
        "OPENGROK_USERNAME": "your-value",
        "OPENGROK_PASSWORD": "your-value",
        "OPENGROK_VERIFY_SSL": "your-value",
        "OPENGROK_CODE_MODE": "your-value",
        "OPENGROK_ENABLE_MEMORY_TOOLS": "your-value",
        "OPENGROK_DEFAULT_PROJECT": "your-value",
        "OPENGROK_CONTEXT_BUDGET": "your-value",
        "OPENGROK_API_VERSION": "your-value",
        "HTTP_PROXY": "your-value",
        "OPENGROK_RESPONSE_FORMAT_OVERRIDE": "your-value",
        "OPENGROK_MEMORY_BANK_DIR": "your-value",
        "OPENGROK_LOCAL_COMPILE_DB_PATHS": "your-value",
        "OPENGROK_ENABLE_ELICITATION": "your-value",
        "OPENGROK_ENABLE_SAMPLING": "your-value",
        "OPENGROK_SAMPLING_MODEL": "your-value",
        "OPENGROK_ENABLE_FILES_API": "your-value",
        "OPENGROK_ENABLE_OBSERVATION_MASKER": "your-value",
        "OPENGROK_OBSERVATION_MASKER_TURNS": "your-value",
        "OPENGROK_SAMPLING_MAX_TOKENS": "your-value",
        "OPENGROK_AUDIT_LOG_FILE": "your-value",
        "OPENGROK_RATELIMIT_RPM": "your-value",
        "OPENGROK_PER_TOOL_RATELIMIT": "your-value",
        "OPENGROK_TIMEOUT": "your-value",
        "OPENGROK_DEFAULT_MAX_RESULTS": "your-value",
        "OPENGROK_PASSWORD_FILE": "your-value",
        "OPENGROK_MAX_RESPONSE_BYTES": "your-value",
        "OPENGROK_SEARCH_AND_READ_CAP": "your-value",
        "OPENGROK_STRICT_SSRF": "your-value",
        "OPENGROK_JWT_ISSUER": "your-value",
        "OPENGROK_GRAMMAR_DIR": "your-value"
      }
    }
  }
}

Run this in your terminal

claude mcp add opengrok --env OPENGROK_BASE_URL=your-value --env OPENGROK_USERNAME=your-value --env OPENGROK_PASSWORD=your-value --env OPENGROK_VERIFY_SSL=your-value --env OPENGROK_CODE_MODE=your-value --env OPENGROK_ENABLE_MEMORY_TOOLS=your-value --env OPENGROK_DEFAULT_PROJECT=your-value --env OPENGROK_CONTEXT_BUDGET=your-value --env OPENGROK_API_VERSION=your-value --env HTTP_PROXY=your-value --env OPENGROK_RESPONSE_FORMAT_OVERRIDE=your-value --env OPENGROK_MEMORY_BANK_DIR=your-value --env OPENGROK_LOCAL_COMPILE_DB_PATHS=your-value --env OPENGROK_ENABLE_ELICITATION=your-value --env OPENGROK_ENABLE_SAMPLING=your-value --env OPENGROK_SAMPLING_MODEL=your-value --env OPENGROK_ENABLE_FILES_API=your-value --env OPENGROK_ENABLE_OBSERVATION_MASKER=your-value --env OPENGROK_OBSERVATION_MASKER_TURNS=your-value --env OPENGROK_SAMPLING_MAX_TOKENS=your-value --env OPENGROK_AUDIT_LOG_FILE=your-value --env OPENGROK_RATELIMIT_RPM=your-value --env OPENGROK_PER_TOOL_RATELIMIT=your-value --env OPENGROK_TIMEOUT=your-value --env OPENGROK_DEFAULT_MAX_RESULTS=your-value --env OPENGROK_PASSWORD_FILE=your-value --env OPENGROK_MAX_RESPONSE_BYTES=your-value --env OPENGROK_SEARCH_AND_READ_CAP=your-value --env OPENGROK_STRICT_SSRF=your-value --env OPENGROK_JWT_ISSUER=your-value --env OPENGROK_GRAMMAR_DIR=your-value -- npx -y opengrok-mcp-server

Fill in the empty values before running it.

Open in Cursor

Or copy the settings yourself

Paste into .cursor/mcp.json in your project, or ~/.cursor/mcp.json

{
  "mcpServers": {
    "opengrok": {
      "command": "npx",
      "args": [
        "-y",
        "opengrok-mcp-server"
      ],
      "env": {
        "OPENGROK_BASE_URL": "your-value",
        "OPENGROK_USERNAME": "your-value",
        "OPENGROK_PASSWORD": "your-value",
        "OPENGROK_VERIFY_SSL": "your-value",
        "OPENGROK_CODE_MODE": "your-value",
        "OPENGROK_ENABLE_MEMORY_TOOLS": "your-value",
        "OPENGROK_DEFAULT_PROJECT": "your-value",
        "OPENGROK_CONTEXT_BUDGET": "your-value",
        "OPENGROK_API_VERSION": "your-value",
        "HTTP_PROXY": "your-value",
        "OPENGROK_RESPONSE_FORMAT_OVERRIDE": "your-value",
        "OPENGROK_MEMORY_BANK_DIR": "your-value",
        "OPENGROK_LOCAL_COMPILE_DB_PATHS": "your-value",
        "OPENGROK_ENABLE_ELICITATION": "your-value",
        "OPENGROK_ENABLE_SAMPLING": "your-value",
        "OPENGROK_SAMPLING_MODEL": "your-value",
        "OPENGROK_ENABLE_FILES_API": "your-value",
        "OPENGROK_ENABLE_OBSERVATION_MASKER": "your-value",
        "OPENGROK_OBSERVATION_MASKER_TURNS": "your-value",
        "OPENGROK_SAMPLING_MAX_TOKENS": "your-value",
        "OPENGROK_AUDIT_LOG_FILE": "your-value",
        "OPENGROK_RATELIMIT_RPM": "your-value",
        "OPENGROK_PER_TOOL_RATELIMIT": "your-value",
        "OPENGROK_TIMEOUT": "your-value",
        "OPENGROK_DEFAULT_MAX_RESULTS": "your-value",
        "OPENGROK_PASSWORD_FILE": "your-value",
        "OPENGROK_MAX_RESPONSE_BYTES": "your-value",
        "OPENGROK_SEARCH_AND_READ_CAP": "your-value",
        "OPENGROK_STRICT_SSRF": "your-value",
        "OPENGROK_JWT_ISSUER": "your-value",
        "OPENGROK_GRAMMAR_DIR": "your-value"
      }
    }
  }
}

Your browser asks to open the app, then the app shows the settings and asks you to confirm. Key values are left empty for you to fill in.

Open in VS Code

Or copy the settings yourself

Paste into .vscode/mcp.json in your project

{
  "servers": {
    "opengrok": {
      "type": "stdio",
      "command": "npx",
      "args": [
        "-y",
        "opengrok-mcp-server"
      ],
      "env": {
        "OPENGROK_BASE_URL": "your-value",
        "OPENGROK_USERNAME": "your-value",
        "OPENGROK_PASSWORD": "your-value",
        "OPENGROK_VERIFY_SSL": "your-value",
        "OPENGROK_CODE_MODE": "your-value",
        "OPENGROK_ENABLE_MEMORY_TOOLS": "your-value",
        "OPENGROK_DEFAULT_PROJECT": "your-value",
        "OPENGROK_CONTEXT_BUDGET": "your-value",
        "OPENGROK_API_VERSION": "your-value",
        "HTTP_PROXY": "your-value",
        "OPENGROK_RESPONSE_FORMAT_OVERRIDE": "your-value",
        "OPENGROK_MEMORY_BANK_DIR": "your-value",
        "OPENGROK_LOCAL_COMPILE_DB_PATHS": "your-value",
        "OPENGROK_ENABLE_ELICITATION": "your-value",
        "OPENGROK_ENABLE_SAMPLING": "your-value",
        "OPENGROK_SAMPLING_MODEL": "your-value",
        "OPENGROK_ENABLE_FILES_API": "your-value",
        "OPENGROK_ENABLE_OBSERVATION_MASKER": "your-value",
        "OPENGROK_OBSERVATION_MASKER_TURNS": "your-value",
        "OPENGROK_SAMPLING_MAX_TOKENS": "your-value",
        "OPENGROK_AUDIT_LOG_FILE": "your-value",
        "OPENGROK_RATELIMIT_RPM": "your-value",
        "OPENGROK_PER_TOOL_RATELIMIT": "your-value",
        "OPENGROK_TIMEOUT": "your-value",
        "OPENGROK_DEFAULT_MAX_RESULTS": "your-value",
        "OPENGROK_PASSWORD_FILE": "your-value",
        "OPENGROK_MAX_RESPONSE_BYTES": "your-value",
        "OPENGROK_SEARCH_AND_READ_CAP": "your-value",
        "OPENGROK_STRICT_SSRF": "your-value",
        "OPENGROK_JWT_ISSUER": "your-value",
        "OPENGROK_GRAMMAR_DIR": "your-value"
      }
    }
  }
}

Your browser asks to open the app, then the app shows the settings and asks you to confirm. Key values are left empty for you to fill in.

This one runs on your computer, and ChatGPT can only connect to servers on the internet. Pick another app.

Your choice stays on this device in a cookie; no account needed.

Values you fill in

OPENGROK_BASE_URL required env
OpenGrok server base URL (e.g. https://opengrok.example.com/source/)
OPENGROK_USERNAME env
OpenGrok authentication username. Leave unset for anonymous access.
OPENGROK_PASSWORD secret env
OpenGrok authentication password. Prefer storing via OS keychain using 'npx opengrok-mcp-server setup'.
OPENGROK_VERIFY_SSL env
Verify TLS certificates. Set to false for self-signed or internal CA certs.
OPENGROK_CODE_MODE env
Enable Code Mode: 2-tool sandbox interface with env.opengrok.* JavaScript API. Reduces AI token usage by ~90%.
OPENGROK_ENABLE_MEMORY_TOOLS env
Register the 3 memory tools in Code Mode (memory status, read, update). Off = api + execute only.
OPENGROK_DEFAULT_PROJECT env
Default project to scope all searches. Can be overridden per call.
OPENGROK_CONTEXT_BUDGET env
Response size tier controlling token usage.
OPENGROK_API_VERSION env
OpenGrok REST API version. Use v2 for call graph features (requires OpenGrok 1.12+).
HTTP_PROXY env
HTTP/HTTPS proxy URL for all OpenGrok API requests (e.g. http://proxy.company.com:8080). Also set as HTTPS_PROXY.
OPENGROK_RESPONSE_FORMAT_OVERRIDE env
Force a specific response format for all tools. Leave unset for per-tool auto-selection (recommended).
OPENGROK_MEMORY_BANK_DIR env
Directory where the AI stores investigation notes (active-task.md, investigation-log.md). Defaults to ~/.config/opengrok-mcp/memory-bank/ or workspace-relative when set by the VS Code extension.
OPENGROK_LOCAL_COMPILE_DB_PATHS env
Comma-separated paths to compile_commands.json for C/C++ compiler flag and include-path extraction. Leave unset for automatic workspace discovery.
OPENGROK_ENABLE_ELICITATION env
Interactive AI Prompts — the AI pauses to ask questions during investigations (project selection, file disambiguation). Requires Claude Code v2.1.76+ or a client that supports MCP Elicitation.
OPENGROK_ENABLE_SAMPLING env
AI Sampling — allow the server to request LLM completions for error explanations and summaries. Off by default to avoid consuming premium requests (e.g. GitHub Copilot).
OPENGROK_SAMPLING_MODEL env
Model preference for MCP Sampling (used for error explanation and query reformulation).
OPENGROK_ENABLE_FILES_API env
Files API Cache — avoids re-uploading unchanged investigation notes. Requires Files API support in the MCP client.
OPENGROK_ENABLE_OBSERVATION_MASKER env
Observation Masker — prepend compact history summaries to opengrok_execute results after N turns. Disabled by default; has no benefit for clients that retain full context (Claude Code, Cursor).
OPENGROK_OBSERVATION_MASKER_TURNS env
Number of most-recent opengrok_execute results to keep as full text before masking older ones. Default: 10.
OPENGROK_SAMPLING_MAX_TOKENS env
Maximum tokens for AI sampling responses (error explanation, query reformulation). Range: 64–4096.
OPENGROK_AUDIT_LOG_FILE env
Path to write structured audit events (CSV/JSON). Appends tool invocations, elicitation events, and errors. Leave unset to disable.
OPENGROK_RATELIMIT_RPM env
Maximum requests per minute to the OpenGrok server. Default: 60.
OPENGROK_PER_TOOL_RATELIMIT env
Per-tool rate limits in requests per minute, as comma-separated tool:rpm pairs (e.g. opengrok_execute:15,opengrok_search_code:30). Overrides OPENGROK_RATELIMIT_RPM for specific tools.
OPENGROK_TIMEOUT env
HTTP request timeout in seconds for OpenGrok API calls. Increase for slow servers. Default: 30.
OPENGROK_DEFAULT_MAX_RESULTS env
Default maximum number of results returned per search query. Default: 25.
OPENGROK_PASSWORD_FILE env
Path to a file containing the OpenGrok password (file-mounted secret for containers). Takes precedence over the OS keychain when OPENGROK_PASSWORD is unset.
OPENGROK_MAX_RESPONSE_BYTES env
Hard cap on response payload size in bytes. Overrides the context-budget default. Non-positive values are ignored.
OPENGROK_SEARCH_AND_READ_CAP env
Cap for the search_and_read compound tool in bytes. Overrides the context-budget default (2–8 KB depending on tier). Non-positive values are ignored.
OPENGROK_STRICT_SSRF env
When true, reject OPENGROK_BASE_URL values pointing at private/loopback IPs at startup. Default: false (warn only; per-request guards still apply).
OPENGROK_JWT_ISSUER env
Expected JWT issuer (iss claim) for HTTP transport OAuth. When set, JWTs from other issuers are rejected.
OPENGROK_GRAMMAR_DIR env
Directory containing tree-sitter WASM grammars. Overrides the bundled grammar lookup.

These settings are generated from the maker’s registry entry. If the README says otherwise, follow the README.

What it can do

Runs on your computer; the tool list appears in your AI app after you install it.

Basic checksi

We check information anyone can see; we have not read the code. Checks that do not apply are left out of the count. · Checked Nov 8, 2026

✓ Pass
Maker matches the repo
The registry name was verified with the GitHub account IcyHot09, which owns the repo
… Not checked yet
Still maintained
We have not read this repo from GitHub yet
… Not checked yet
Has a licence
We have not read this repo from GitHub yet
– Not applicable
Endpoint responds
This one runs on your computer; there is no internet endpoint
– Not applicable
Sign-in with OAuth
Runs on your computer and uses local settings instead
… Not checked yet
No hidden instructions in tool descriptions
Runs on your computer; we can only read tool lists from internet endpoints

Compared with others in Search & AI memoryi

More stars than 0% of the other 5722 servers in this category
Published to the registry more recently than 43% of the other 5722 servers in this category
Basic checks equal to or better than 100% of the other 5722 servers in this category

Compared with every active server in this category in the registry. Stars count only when the publisher owns the repo.

Common questions

Is OpenGrok MCP Server safe?

It passed 1 of 1 applicable basic checks. We have not read the code. Before adding a key or token, see what access the server asks for and use a key with only the permissions you need.

What keys or codes does it need?

You need to fill in: OPENGROK_BASE_URL, OPENGROK_PASSWORD

Does it run on my computer or in the cloud?

It runs on your computer. Your AI app starts it when needed, and data does not pass through the maker’s servers (unless it calls an online service itself).

Is it still maintained?

The GitHub repo last changed –, and the latest version (9.6.0) reached the registry 2 months ago.

Which apps can use it?

Apps that support MCP, such as Claude Desktop, Claude Code, Cursor and VS Code. You also need Node.js on your computer.

What can I use instead?

In the same category: Context7, Codebase Memory, Exa

Alternatives

Servers in the same category from other makers, sorted by stars.

Reading a card:↓ Downloads per weeki★ GitHub starsiThree pillars: reviews · checks · usageiUpdated = latest version published to the registryi

Context7

Feeds AI the latest docs for libraries and frameworks before it answers, so code it writes does not use outdated, removed functions.

by upstashWidely used↓ 972.7K/wk★ 64.2KUpdated 2 days ago

Computer or cloud

Install

Codebase Memory

Codebase knowledge graph for AI agents — 162 languages, sub-ms queries, 99% fewer tokens.

by DeusDataWidely used↓ 18K/wk★ 48.1KUpdated 22 days ago

Runs on your computer

Install

Exa

Connect AI agents to Exa for web search, content fetching, and multi-step research.

by exa-labsWidely used★ 5.2KUpdated 2 months ago

Runs in the cloud✓ exa.ai

Install

README from the maker

Open the README

Copied from the maker’s repo as written. PopNx MCP has not reviewed or endorsed it. HTML, images and scripts are removed. Links lead off this site.

OpenGrok MCP Server

Code intelligence for any OpenGrok-indexed codebase — search, read, blame, symbol navigation, diffs, commit history, call graphs, dependency maps, and guided investigation. Optimized for token efficiency through Code Mode and AST-aware code reads.

Quick Start

Option 1 — VS Code Extension

Install OpenGrok MCP from the VS Code Marketplace, or search "OpenGrok" in the Extensions panel. The configuration panel opens on first launch — enter your OpenGrok endpoint, username, and password, then click Save Settings and reload when prompted.

The extension provides a visual configuration UI and manages the MCP server process automatically. No Python, external Node.js install, or manual environment setup required.

Option 2 — npm / npx CLI

npm install -g opengrok-mcp-server

opengrok-mcp setup # interactive wizard: URL, credentials, MCP client registration

Or run without installing:

npx opengrok-mcp-server setup

Other CLI commands:

opengrok-mcp status      # health check: validates connectivity and detects installed MCP clients

opengrok-mcp setup --test # test the stored connection without the wizard opengrok-mcp setup --set contextBudget=generous # update one stored setting non-interactively opengrok-mcp export-audit --format json --output audit.jsonl # export the audit log opengrok-mcp version # print version and exit opengrok-mcp help # show all commands

Works with any MCP-compatible client (CLI or IDE). See MCP_CLIENTS.md for config format and troubleshooting.

Credentials are stored in the OS keychain (macOS Keychain, Windows Credential Manager, Linux libsecret) with an AES-256-GCM encrypted file fallback for headless environments.

[!TIP]

Automatic Updates — The extension checks GitHub for new releases once per 24 hours and notifies you when one is available. Use OpenGrok: Check for Updates to check on demand.

The Problem

Engineers working in large codebases face a specific gap when using AI coding assistants. The model's context window contains the file currently open, the conversation, and whatever has been manually shared — but a production codebase has structure, history, and cross-module relationships that exist entirely outside that window.

A symbol defined in one module and called from seventy others. A function whose behavior only becomes clear from the three commits that shaped it. An include chain stretching across a dozen directories. A call graph showing which components depend on a service before it gets refactored.

Without access to the code index, the model fills these gaps by guessing: it fabricates file paths, invents function signatures, misattributes changes to authors. The model is not wrong because it is unintelligent — it is wrong because it is isolated.

OpenGrok already solves this for human engineers. It indexes source in dozens of programming languages, maintains a full-text index across committed history, and exposes definition lookups, reference graphs, blame, directory traversal, and file history through a REST API. The problem was that AI tools had no way to reach it.

How It Works

┌──────────────────────────────────────────────────────┐

│ AI Client (Claude, Copilot, Cursor, Codex …) │ └─────────────────────┬────────────────────────────────┘ │ MCP (stdio or HTTP) ┌─────────────────────▼────────────────────────────────┐ │ OpenGrok MCP Server (Node.js) │ │ opengrok_api ──── full API spec, once per session │ │ opengrok_execute ─ run JavaScript in sandbox │ │ │ │ OpenGrok client ── search · symbols · blame · diffs │ └─────────────────────┬────────────────────────────────┘ │ HTTP (REST + web fallback) ┌─────────────────────▼────────────────────────────────┐ │ OpenGrok │ │ search · symbols · call graphs · index health │ └──────────────────────────────────────────────────────┘

The server exposes two primary tools. opengrok_api delivers the full API specification at session start. Every subsequent operation goes through opengrok_execute: the AI writes a JavaScript program using the env.opengrok.* object — search, getFileContent, getFileAnnotate, getFileHistory, browseDir, getFileSymbols — and submits it as a single execution.

Intermediate results stay inside the sandbox; only the final return value crosses back to the context window. A complete investigation — find the symbol, read the definition, check who changed it, trace the callers — is one script, not a sequence of round-trips with results flowing through the context between each. Token savings of 80–95% are typical for complex investigations.

All env.opengrok.* calls appear synchronous inside sandbox code — the QuickJS WASM VM bridges async HTTP calls transparently over a SharedArrayBuffer + Atomics channel (8 MB data region, 62 s per-call timeout, 62 s hard execution cap), while keeping the Node.js event loop free.

Memory bank — two files persist across turns and session restarts: active-task.md (4 KB) for current investigation state and investigation-log.md (32 KB) for append-only findings. Inside the sandbox: env.opengrok.readMemory() / env.opengrok.writeMemory(). See the Memory Bank reference below.

Reference

Tool Reference

31 tools total: 2–5 in Code Mode (opengrok_api + opengrok_execute, plus 3 memory tools when OPENGROK_ENABLE_MEMORY_TOOLS=true) and 26 in standard mode (OPENGROK_CODE_MODE=false).

Primary Tools

Tool	Purpose
`opengrok_search_code`	Full-text, definition, reference, path, and history search. Supports `file_type` filtering and `cursor` pagination.
`opengrok_find_file`	Locate files by name or directory pattern. Supports `cursor` pagination.
`opengrok_get_file_content`	Read source code. Use `start_line` / `end_line` for large files.
`opengrok_get_file_history`	Commit history for a file. Supports `cursor` pagination.
`opengrok_browse_directory`	View folder structure and contained files. Supports `cursor` / `limit` pagination.
`opengrok_list_projects`	List all indexed repositories.
`opengrok_get_file_annotate`	Line-by-line blame annotation. Supports `revision`, `start_line`/`end_line` range, `includeContent`.
`opengrok_get_file_symbols`	Extract classes, functions, macros, and structs from a file. Supports `cursor` pagination.
`opengrok_search_suggest`	Query autocomplete recommendations. Supports `context` passthrough for ranking.

Compound Tools

These merge multiple API calls into a single operation.

Tool	What it replaces	Savings
`opengrok_get_symbol_context`	Search definition + read source + fetch headers + get references	~92% fewer tokens
`opengrok_search_and_read`	Search + read surrounding context (cap: `OPENGROK_SEARCH_AND_READ_CAP`)	~92% fewer tokens
`opengrok_batch_search`	2–5 parallel searches, deduplicated results	~73% fewer tokens
`opengrok_index_health`	Latency, connectivity, staleness score	Diagnostic

Investigation Tools

Tool	Purpose
`opengrok_what_changed`	Recent line changes grouped by commit — author, date, SHA, changed lines with context
`opengrok_dependency_map`	BFS traversal of `#include`/`import` chains up to depth 3; directed graph with `uses`/`used_by`
`opengrok_search_pattern`	Regex code search; returns `file:line:content` matches
`opengrok_blame`	Blame with line range (`line_start` / `line_end`) and optional diff
`opengrok_call_graph`	Call chain tracing via OpenGrok API v2 (requires `OPENGROK_API_VERSION=v2`; refs-based fallback on v1)
`opengrok_get_file_diff`	Unified diff between two revisions with context lines
`opengrok_get_compile_info`	C/C++ compiler flags and include paths from local `compile_commands.json`
`opengrok_get_all_matches`	All matching lines in a file when search shows truncated hits
`opengrok_get_file_history_with_files`	Commit history with co-changed file lists via RSS feed
`opengrok_get_download_url`	Direct download URL for a file (no HTTP call)
`opengrok_list_groups`	Project groups (empty when admin auth required)
`opengrok_get_suggest_popularity`	Popular suggestions for a project field (empty when admin auth required)
`opengrok_get_project_repositories`	Repositories for a project (empty when admin auth required)

*(Note: search tools support language filtering. Pass file_type using the canonical analyzer name — cxx for C++, golang for Go, sh for shell, javascript for JS. Aliases accepted: cpp/c++→cxx, go→golang, bash/shell→sh, js→javascript, ts→typescript, cs→csharp, py→python, rb→ruby, rs→rust.)*

defs/refs/symbol fallback notes — defs, refs, and symbol searches require a project scope (pass projects or set OPENGROK_DEFAULT_PROJECT); without one they may return too many cross-project hits. On instances where the REST endpoint returns an error or empty results for these types, the client automatically falls back to web-UI parsing so the LLM still gets answers. opengrok_call_graph needs API v2 and degrades to a refs-based view on v1.

Code Mode API

Set OPENGROK_CODE_MODE=true (the default). Call opengrok_api once at session start to receive the full API spec. All subsequent operations go through opengrok_execute.

All sandbox API calls are synchronous — flat globals (search(...)), no await. The env.opengrok.* object form (env.opengrok.search(...)) is equivalent.

Search & Discovery

Method	Returns
`env.opengrok.search(query, opts?)`	Full text, defs, refs, symbol, path, hist. Opts: `searchType`, `projects`, `maxResults` (default 5), `startIndex`, `cursor`, `fileType`, `sort`, `maxHitsPerFile`, `dir`, `pathFilter`, `file`, `expandFunction`
`env.opengrok.batchSearch(queries[], opts?)`	One result-set per query (max 10), run in parallel on the host. Per-query `expandFunction: true` includes enclosing function context
`env.opengrok.findFile(pattern, opts?)`	`{ totalCount, results: [{project, path}], cursor? }`
`env.opengrok.searchSuggest(query, opts?)`	`{ query, field, suggestions, time }`. Opts: `field`, `project`/`projects`, `context` (other-field values for ranking)
`env.opengrok.getAllMatchesInFile(project, path, query, opts?)`	All matching lines in a file when search results show truncated hits. Also used automatically when `search()` is given a `file:` filter (no pagination)

search() uses canonical file type names only (e.g. cxx, golang, sh) — see the alias list above. Pass expandFunction: true to expand matching results to their enclosing function body (adds host-side reads, up to 3 files per call).

Cursor pagination — Methods that return a cursor field (search, findFile, browseDir, getFileSymbols, getFileHistory, `getFileDif

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OpenGrok MCP Server

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OpenGrok MCP Server

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