Qector Claude Plugin MCP Server

QECTOR Claude Plugin

QECTOR is a local, fail-closed quantum error correction (QEC) integration for Claude Code and Claude Desktop, built on qector-decoder-v3==1.0.0 and the QECTOR Decoder v3 Reference Manual (DOI: 10.5281/zenodo.21941046). Every correction returned by this plugin is verified against H c = s (mod 2) before it leaves the local server, and the default operation makes no network request.

4 MCP servers · 8 stable / 29 research / 3 admin tools · 11 commands · 5 agents · 28 skills · zero-egress default

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🚀 Quick Start

1. Install the runtime

git clone https://github.com/GuillaumeLessard/qector-claude-plugin.git
cd qector-claude-plugin
python -m pip install -r requirements.txt
python scripts/qector_runtime_check.py

2. Install as a Claude Code marketplace plugin

claude plugin marketplace add GuillaumeLessard/qector-claude-plugin
claude plugin install qector@qector-tools

The default install exposes only qector-library (8 stable tools). Opt-in research and admin surfaces are added explicitly — see the trust-zone table below.

3. Install the local Claude Desktop extension (Windows / macOS / Linux)

The Claude Desktop manifest lives under .claude-desktop-extension/ and points at mcp/mcp_server_desktop.py --profile safe. The local installer records the exact Python interpreter used, so Windows PATH ambiguity cannot break the install:

python scripts/configure_claude_desktop.py --check-only   # dry run
python scripts/configure_claude_desktop.py --confirm      # write config

A native Windows command is also shipped:

.\scripts\install_windows_connector.cmd

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🔬 What ships in this release

MCP servers (4)

qector-library is the authoritative default surface. Every tool on it verifies its output before returning: syndrome decoders check H c = s (mod 2), threshold sweeps ship Wilson 95% intervals with SHA-256-stamped JSON artifacts, and build_code_from_matrix validates dimensions and code family before allocating a parity-check matrix.

The research and admin servers are never auto-enabled. They are added only by an explicit --with-research or --with-admin flag combined with a confirm=true argument on every call.

Commands (11)

/qec-setup, /qec-facts, /qec-theorem, /qec-reproduce, /qec-threshold-sweep, /qec-wilson, /qec-dem, /qec-code-inspect, /qec-benchmark, /qec-sinter, /qec-validate-mcp.

Agents (5)

qec-researcher, qec-developer, qec-validator, qec-sysadmin, qec-hardware-engineer.

Skills (28)

qector-core, qector-architecture, qector-math-foundations, qector-codes-builder, qector-bp-osd, qector-two-stage-css, qector-space-time, qector-decoders-deep-dive, qector-dem-pipeline, qector-sinter, qector-ler-methodology, qector-pymatching-compat, qector-batch-decoding, qector-orchestration, qector-reproducibility, qector-testing-strategy, qector-deployment, qector-release-engineering, qector-licensing, qector-services, qector-glossary, qector-educator, qector-researcher, qector-developer, qector-sysadmin, qector-hardware-engineer, qector-roadmap, qector-workbench.

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🛡️ Trust zones

The 40 tools split into three named trust zones, plus the Desktop safe profile which re-exports the 8 stable tools through a separate adapter. No tool calls the network by default.

Per-tool call budgets

The MCP processes enforce their own ceilings because there is no external rate limiter. The defaults are intentionally conservative; every ceiling is overridable per-tool with QECTOR_MCP_MAX_CALLS_<TOOL_NAME> and disable-able with -1.

Exhaustion returns RESOURCE_LIMIT and the process stays up. See SECURITY.md for the input-size ceilings (QECTOR_MCP_MAX_DISTANCE, QECTOR_MCP_MAX_TRIALS, QECTOR_MCP_MAX_SWEEP_POINTS, QECTOR_MCP_MAX_MATRIX_CELLS).

What this plugin does NOT do

• It does not transmit syndromes, parity matrices, circuits, or tool arguments anywhere by default. The only outbound network operation is the explicit opt-in PyPI freshness check (compat_report(check_pypi=true) / env_block(check_pypi=true)); it checks the published package version only and caches the response for the server process. See PRIVACY.md.
• It does not run untrusted code. The three tools classified as "Execute" (decode_single, threshold_sweep, build_code_from_matrix) perform scoped QEC math on caller-supplied binary inputs. They never spawn subprocesses, never load dynamic modules, and never read or write outside QECTOR_ARTIFACT_DIR.
• The four "Write" tools are limited to: writing the matrix file the caller just built (code_export_matrices), writing the local Claude Desktop config (configure_claude_desktop, requires confirm=true), and writing a hashed artifact under the configured artifact directory (artifacts_sha256 / artifact_metadata_check). None touch arbitrary filesystem paths or remote endpoints.

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🏗️ Architecture

                  QECTOR Claude Plugin v1.0.4
   ┌──────────────┐ ┌──────────────┐ ┌────────────────┐
   │ 11 Commands  │ │  5 Agents    │ │   28 Skills    │
   └──────┬───────┘ └──────┬───────┘ └────────┬───────┘
                          │
                          ▼
   ┌──────────────────────────────────────────────┐
   │  qector-library   MCP   8 stable tools       │  default
   │  qector-research  MCP  29 provisional tools  │  opt-in
   │  qector-admin     MCP   3 privileged tools   │  opt-in
   │  qector-desktop-mcp     8 safe-profile tools │  Desktop
   └──────────────────────┬───────────────────────┘
                          │  local stdio, zero egress
                          ▼
              ┌────────────────────────┐
              │  qector-decoder-v3     │
              │  1.0.0  (Rust/PyO3)    │
              └────────────────────────┘

The four servers share mcp/qector_mcp_contract.py, which enforces the result envelope (status, tool, server, version), the closed list of stable error codes, and the fail-closed default for every operation.

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📥 Download artifacts

The canonical 1.0.4 release assets live in dist/, each with a SHA-256 sidecar and a combined SHA256SUMS file:

qector-claude-desktop-1.0.4.mcpb is the artifact listed in server.json and is the one Claude Desktop's MCP Registry downloads.

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📋 System requirements

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📚 Documentation

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🛠️ Development and release

python -m unittest discover -s tests -v          # mathematical + protocol tests
python scripts/validate_source.py                 # source-only structural check
python scripts/validate_plugin_bundle.py          # built-bundle check
python scripts/release_validate.py                # version + manifest cross-check
ruff check .                                      # lint
python scripts/build_release.py --all             # build all artifacts

Build the installable Desktop .mcpb on each target platform with an approved runtime environment:

python scripts/build_release.py --desktop --runtime-root <venv>

The builder is deterministic: a fixed DOS timestamp is stamped on every zip entry so the artifact hashes are stable across rebuilds.

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📄 License

Proprietary — Copyright © 2026 Guillaume Lessard / iD01t Productions. See LICENSE.md.

The underlying qector-decoder-v3 backend is separately licensed:

• ✅ Free for personal, academic, educational, and non-commercial research.
• 💼 Commercial use (company R&D, SaaS, hosted API, OEM, redistribution) requires a paid license — see qector.store/pricing.
• 🔄 60-day commercial evaluation, creditable against a license.

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🤝 Support & Contact

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