ParaView MCP Server

This package is the external FastMCP server that talks to the ParaView MCP plugin over TCP.

It expects the ParaView-side C++ plugin to be loaded and listening first.

Requirements

• Python >=3.13
• fastmcp>=4.0.3,<5

Install

Run without installing (recommended):

uvx paraview-mcp-server

Or install the command from PyPI:

uv tool install paraview-mcp-server

For development, install in editable mode from the repository:

cd Wrapping/Python/MCPServer
uv sync

Optional Environment Configuration

• PARAVIEW_HOST defaults to 127.0.0.1; set it for remote connections
• PARAVIEW_PORT defaults to 9877
• PARAVIEW_AUTH_TOKEN is required for non-loopback targets
• PARAVIEW_CONNECT_TIMEOUT_SECONDS defaults to 30
• PARAVIEW_COMMAND_TIMEOUT_SECONDS is unset by default, allowing long commands to finish

Execution and state

One command runs at a time, up to three wait in FIFO order, and further calls report busy. This prevents concurrent mutations of ParaView's shared state.

Cancelled waiters never execute; cancelling an active call does not stop ParaView. execute_paraview_code separates request_status from execution_status and retains the success field. An outcome_unknown blocks further commands until the MCP server restarts; inspect ParaView first and never retry automatically.

Python variables and history persist across calls on the same bridge connection. Disconnecting or reconnecting resets them without undoing pipeline changes or external side effects.

Bridge protocol

FastMCP 4 supports MCP 2026-07-28 and legacy clients over stdio with the same tools.

The server speaks protocol version 2 to the ParaView plugin and sends:

• hello
• ping
• execute_python
• inspect_pipeline
• capture_screenshot

The public MCP tools remain:

• execute_paraview_code
• get_pipeline_info
• get_screenshot

Run

paraview-mcp-server