MCP Servers

A collection of standalone Model Context Protocol servers written in Go. Each server is independently buildable and installable — pick only what you need. Released under the MIT No Attribution License.

Available Servers

Server	Description	CGO
markitdown	Convert documents to Markdown (HTML, PDF, DOCX, XLSX, PPTX, images)	No
kg	Project knowledge graph — store and query code entities across sessions. Supports multi-scope graphs for monorepos, federated across layers, plus a personal store. Renders as mermaid or Graphviz diagrams with kg graph. Graphs can also be pushed to a shared hub (kg hub serve) and searched from other projects as remote layers.	Yes

Plus one shared library, not installed as a binary:

Library	Description
kglib	KuzuDB schema, entity/relation/observation CRUD, hybrid search, embedders, and the FederatedStore that merges results across multiple KG databases

graph LR
    Client["MCP Client\n(Claude Code / Claude Desktop)"]
    MD["markitdown-mcp\nDocument converter"]
    KG["kg\nKnowledge graph"]
    KGDB[(".ai/knowledge.db\nper project")]
    PERSONAL[("~/.kg/knowledge.db\nper user")]
    HUB["kg hub serve\nshared hub, per org"]

    Client -->|stdio| MD
    Client -->|stdio| KG
    KG --> KGDB
    KG -->|"--personal / --with-personal"| PERSONAL
    KG -->|"HTTP: kg push / remotes"| HUB

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Each server is a self-contained Go binary with its own go.mod. No server depends on another; kg uses the kglib library via a local replace directive.

Quick Install

# Install all servers
curl -fsSL https://raw.githubusercontent.com/Cortexa-LLC/mcp/main/install.py | python3

# Install a specific server
curl -fsSL https://raw.githubusercontent.com/Cortexa-LLC/mcp/main/install.py | python3 - --mcp kg
curl -fsSL https://raw.githubusercontent.com/Cortexa-LLC/mcp/main/install.py | python3 - --mcp markitdown

# From a clone
python3 install.py --mcp kg
python3 install.py --mcp markitdown
python3 install.py              # installs all

Install dir defaults (override with --prefix DIR or INSTALL_DIR=...):

Platform	Default
macOS	/usr/local/bin
Linux	/usr/local/bin (may need sudo)
Windows	%LOCALAPPDATA%\Programs\mcp

Manual Build (per server)

cd src/markitdown && make install
cd src/kg         && make install          # requires a C compiler (CGO)

make install                               # from the repo root: both servers
make test                                  # kglib + all servers

Prerequisites

• Go 1.24+ — install
• kg only: C compiler — Xcode CLT on macOS (xcode-select --install), gcc/clang on Linux
• markitdown OCR (optional): Tesseract 5+ (brew install tesseract)

MCP Configuration

After installing, add the servers to your MCP client:

Claude Desktop

{
  "mcpServers": {
    "markitdown": {
      "command": "/usr/local/bin/markitdown-mcp"
    },
    "kg": {
      "command": "/usr/local/bin/kg",
      "args": ["server", "--stdio"]
    }
  }
}

Config file locations:

• macOS: ~/Library/Application Support/Claude/claude_desktop_config.json
• Linux: ~/.config/Claude/claude_desktop_config.json
• Windows: %APPDATA%\Claude\claude_desktop_config.json

Claude Code (.mcp.json in project root)

Recommended for kg — place .mcp.json in each project root so Claude Code spawns kg with the correct working directory, ensuring it opens that project's .ai/knowledge.db and not another project's graph.

{
  "mcpServers": {
    "markitdown": { "command": "/usr/local/bin/markitdown-mcp" },
    "kg":         { "command": "/usr/local/bin/kg", "args": ["server", "--stdio"] }
  }
}

markitdown is stateless and can be configured globally in ~/.claude/settings.json if preferred.

Server Details

• markitdown — No CGO, no system dependencies for core formats. OCR for images requires Tesseract (optional, degrades gracefully). → Integration guide

• kg — Requires CGO (bundles KuzuDB statically). Each project gets its own isolated graph at .ai/knowledge.db, auto-discovered by walking up the directory tree. Monorepos can split the graph into scopes that federate across layers. Supports OpenAI or Ollama embeddings for semantic search (optional). Also keeps a personal store (kg personal init) for knowledge that follows you between repositories, searchable alongside a project's graph with --with-personal or via the search_personal_knowledge MCP tool. Agents can record to it only when explicitly enabled with --personal-writes. → CLI reference · Scopes & federation · Personal store · Integration guide & CLAUDE.md patterns

• kglib — Shared library, not a server. Owns the schema, search, embedders, Cypher read-only guard, and FederatedStore. Read this before changing storage or federation behaviour in either graph.

Docs

Document	Description
docs/kg-cli-reference.md	Full kg CLI reference — all commands, flags, entity types, Cypher examples
docs/kg-scopes.md	Multi-scope monorepo graphs and federated (layered) search — configuration and commands
docs/kg-scopes-implementation.md	How scopes and federation are implemented internally
docs/kg-graph-linking-design.md	Design and measurement behind cross-layer entity linking in kg graph --federated — why the old (name, type) join was wrong and what replaced it
docs/kg-personal-store.md	The personal knowledge store — creating it, writing to it, and federating it into project searches
docs/kg-shared-service.md	The shared knowledge hub — running it, seeding it with kg push, and searching hub graphs from other projects via remotes
docs/kg-shared-service-design.md	The hub's original design proposal — architecture, threat model, and hosting options
src/kglib/README.md	kglib library API, including FederatedStore merge semantics
skills/README.md	Claude Code skills built on these servers, and how to install them
docs/kg-log-plugins.md	Log-file indexing plugins — how a plugin is matched to a log format, and how to add one
docs/kg-claude-integration.md	KG patterns for CLAUDE.md, reducing re-investigation, decision logging, cross-session checkpointing
docs/markitdown-claude-integration.md	Reading PDFs, DOCX, spreadsheets, and URLs; combining with the KG
CHANGELOG.md	Notable changes since v0.1.0