mcpGraph

MCP server that executes directed graphs of MCP server calls.

📖 Learn More: Read mcpGraph: A No-Code Alternative to “Code Mode” to understand how mcpGraph provides the context efficiency and accuracy of Code Mode while maintaining the security and observability of a no-code solution.

🎥 Watch the Demo: Check out the mcpGraph Overview and mcpGraphUX Demo video to see mcpGraph in action and explore the visual debugging capabilities of mcpGraphUX.

🎥 Watch the Demo: Check out the mcpGraphToolkit Deep Dive video to see an agent autonomously build, test, and deploy orchestration tools—“Code Mode” without the code.

Overview

mcpGraph is an MCP (Model Context Protocol) server that exposes tools defined by declarative YAML configurations. Each tool executes a directed graph of nodes that can call other MCP tools, transform data, and make routing decisions, all without embedding a full programming language.

Key Features:

• Declarative Configuration: Define tools and their execution graphs in YAML
• Data Transformation: Use JSONata expressions to transform data between nodes
• Conditional Routing: Use JSON Logic for conditional branching
• Observable: Every transformation and decision is traceable
• No Embedded Code: All logic expressed using standard expression languages (JSONata, JSON Logic)

Related Tools:

• mcpGraphUX: A visual debugging and development environment for mcpGraph. Visualize graph structures, animate through active nodes during execution, set breakpoints, and inspect node inputs and outputs. See the mcpGraphUX repository for details.
• mcpGraphToolkit: An MCP server that provides tools for building, testing, and managing mcpGraph tools. Use it to discover available MCP servers, test expressions, and create graph tools interactively. See mcpGraphToolkit Overview for details.

Example

Here’s a simple example that counts files in a directory:

version: "1.0"

# MCP Server Metadata
server:
  name: "fileUtils"
  version: "1.0.0"
  title: "File utilities"
  instructions: "This server provides file utility tools for counting files and calculating total file sizes in directories."

# Optional: Execution limits to prevent infinite loops
executionLimits:
  maxNodeExecutions: 1000      # Maximum total node executions (default: 1000)
  maxExecutionTimeMs: 300000   # Maximum execution time in milliseconds (default: 300000 = 5 minutes)

# MCP Servers used by the graph
mcpServers:
  filesystem:
    command: "npx"
    args:
      - "-y"
      - "@modelcontextprotocol/server-filesystem"
      - "./tests/counting"

# Tool Definitions
tools:
  - name: "count_files"