Materials MCP Commons

Materials MCP Commons is an open, interoperable foundation for exposing materials-science data, simulations, workflows, and computing capabilities through the Model Context Protocol (MCP).

The project is being built around six invariants:

• a plugin-agnostic engine before any provider- or solver-specific plugin;

• real, provenance-traceable scientific data and real scientific systems;

• versioned, language-neutral contracts before backend-specific adapters;

• focused federated servers rather than one unrestricted server;

• bounded model context through progressive capability discovery and artifact references;

• evidence-backed Conformant, Verified, and Validated trust levels.

Status

Active development. No production-alpha release has been published yet.

The first release is intended to be a research-grade production alpha with a deliberately bounded, evidence-complete capability set. Alpha denotes API and scope evolution; it does not relax scientific-validity, provenance, security, or reproducibility requirements.

Related MCP server: production-grade-mcp-agentic-system

Engine-first scope

• Materials MCP Profile and conformance tooling

• Generic plugin manifest, lifecycle, dispatch boundary, and Scientist Kit

• Context Gateway minimum

• Shared artifact, structure, and durable-run services

• Generic effect, permission, plan, provenance, and policy enforcement

• Production packaging, observability, recovery, and host interoperability

The engine was implemented and gated before the first concrete integration was selected. Concrete plugins are separately packaged and must not become dependencies or special cases in the engine core. The active first proof is the separate full OPTIMADE integration under plugins/optimade/; it uses only real providers and provenance-traceable data. Mocked scientific backends and fabricated scientific results are not accepted as implementation or release evidence.

Documentation

Public documentation begins in docs/.

The repository now contains:

• an installable, typed Python alpha package with audited generic JSON Schema runtime dependencies;

• the immutable 0.1.0 contract line and additive 0.2.0 successor, each with a checksum-pinned resource index;

• an offline, fail-closed conformance harness;

• a deterministic multi-version conformance report and structural zero-coupling audit;

• strict offline profile/package validation and deterministic registration, discovery, inspection, and activation leases;

• exact-owner dispatch with immutable typed requests, two-sided schema validation, and contract-valid structured failures;

• deterministic operation plans, exact scoped permissions, expiring single-use approvals, atomic quotas, atomic at-most-once receipt redemption, and tamper-evident policy audit;

• canonical context measurement with identified host tokenizers, bounded linting, real-source compact projection, retrieval evaluation, and long-session lease checks;

• deterministic empty-workspace scaffolding and exact-profile declarative package building without generated capabilities, handlers, or scientific results;

• deterministic plugin-package and versioned compatibility reports, explicit migration assessment, and manifest-derived capability references without plugin-code execution;

• durable owner-isolated run events, reconnect/cancellation, and hash-verified artifact/provenance records;

• an optional official-SDK MCP adapter with four bounded tools, trusted host-side identity/authorization injection, and real in-process/stdio protocol tests;

• metadata-only operational events, bounded health metrics, and integrity-checked non-overwriting SQLite state snapshots/restores;

• one registered real positive scientific record, its lossless successor migration and bounded compact projection, and an isolated generated-negative rejection corpus; and

• an independently deployable Cloudflare Worker boundary for the canonical schema hostname; and

• the separately packaged, exact-profile OPTIMADE integration contract, with seven bounded capabilities and no provider coupling in the engine.

Start with the runtime guide, production-alpha API compatibility guide, support boundary, MCP host guide, operations runbook, state recovery guide, threat model, Scientist Kit authoring guide, contract guide, versioning policy, scientific evidence policy, and schema-hosting guide. Effectful dispatch is available only through the exact policy boundary; remote scheduling and network-host authentication are not implemented. The OPTIMADE integration's checked support matrix separates local observations from immutable-commit hosted evidence. The hosted matrix and manual live-provider run pass for runtime commit 071b341da1766388689be92f74a894444970e493; no package release or Validated claim is made.

Author and maintainer

Hesham Salama

Licensing

Source code is licensed under the Apache License 2.0. Project-authored documentation and specifications are licensed under CC BY 4.0. Third-party dependencies, datasets, models, and scientific systems retain their own terms.