# Pymatching Decoder

> Minimum-weight perfect matching decoder skill for surface code error correction

- Skill: `a5c-ai/pymatching-decoder` (Agent Skill)
- Install (CLI): `npx skillmds@latest add a5c-ai/pymatching-decoder`
- Raw SKILL.md: https://api.skillmd.com/api/skills/a5c-ai/pymatching-decoder/raw
- Safety review: pending (external: skill-scanner PASS, skillspector PASS)
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Coding & Dev Tools
- Author: a5c-ai (https://skillmd.com/u/a5c-ai)
- Updated: 2026-09-09
- Page: https://skillmd.com/skills/a5c-ai/pymatching-decoder

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# PyMatching Decoder

## Purpose

Provides expert guidance on minimum-weight perfect matching decoding for surface codes and other topological quantum error correction codes.

## Capabilities

- MWPM decoding for surface codes
- Weighted edge matching
- Detector error model processing
- Logical error rate calculation
- Integration with Stim simulations
- Custom graph construction
- Belief propagation integration
- Parallelized decoding

## Usage Guidelines

1. **Graph Construction**: Build matching graph from detector error model
2. **Weight Assignment**: Configure edge weights based on error probabilities
3. **Decoding Execution**: Run MWPM algorithm on syndrome data
4. **Error Analysis**: Calculate logical error rates from decoding results
5. **Optimization**: Tune decoder parameters for specific code structures

## Tools/Libraries

- PyMatching
- NetworkX
- Stim
- NumPy