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PyMCNP skill

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A SKILL.md shipped with PyMCNP that teaches a coding agent to write, scan, run and read MCNP inputs and outputs in Python. By Fusion Science & Ion Beam Technology Group (LBNL).

23 starsUpdated 3 days agoGitHub data from 5 Nov 2026

At a glance

Type
Skill
Works with
MCNP
Tool versions
PyMCNP on Python 3.11 to 3.14; MCNP itself is obtained separately
Operating systems
Not stated in its documentation
Needs a MCNP licence
Yes
AI clients documented
Claude Code
Licence
BSD-3-Clause-LBNL
Language
Python

What it can do

  • Explains PyMCNP's parsing contract, including checking that nothing was left unparsed when an input file is read.
  • Shows how to build cells, surfaces, materials and source cards in Python and generate parameter scans as independent copies of an input.
  • Runs batches of inputs through the mcnp6 executable in separate directories and reports fatal errors per run.
  • Reads OUTP tallies, k-effective and MCNP's ten statistical checks, and streams large PTRAC files event by event.

Limitations

  • Running cases needs your own MCNP installation, which is export-controlled and distributed by RSICC.
  • The skill is a guide to the PyMCNP library; it adds no MCP tools of its own.
  • The authors ask you to review generated models and results before relying on them.

Install

pip install pymcnp

Source: github.com/FSIBT/PyMCNP#installation

MCP servers and skills run code on your computer. Review the source before installing.

AI-generated models, drawings and results must be checked by a qualified engineer before use.