Fortran MCP

Use Fortran MCP to improve AI-assisted Fortran development with cited documentation on language features, compiler behavior, build systems, and the wider ecosystem.

It supports lexical search (matching words), semantic search (matching meaning), and hybrid search (combining both), returning relevant passages with source attribution, version information, and links to the original documentation.

Installation

Requires Python 3.11+ and uv.

uv tool install fortran-mcp

Semantic and hybrid search require additional dependencies:

uv tool install "fortran-mcp[semantic]"

Data bundles are installed automatically on first run. You can also install them beforehand to avoid an initial delay:

fortran-mcp data install core       # for lexical search
fortran-mcp data install semantic   # for semantic and hybrid search

Check installation:

fortran-mcp doctor

Client Setup

<details> <summary>Claude Code</summary>

Use lexical search (default):

claude mcp add --scope user fortran-mcp -- fortran-mcp

Use semantic search:

claude mcp add --scope user fortran-mcp --env FORTRAN_MCP_SEARCH_PROVIDER=semantic -- fortran-mcp

Use hybrid search:

claude mcp add --scope user fortran-mcp --env FORTRAN_MCP_SEARCH_PROVIDER=hybrid -- fortran-mcp

To change the search mode, remove the existing entry first:

claude mcp remove --scope user fortran-mcp

</details> <details> <summary>Codex</summary>

Use lexical search (default):

codex mcp add fortran-mcp -- fortran-mcp

Use semantic search:

codex mcp add fortran-mcp --env FORTRAN_MCP_SEARCH_PROVIDER=semantic -- fortran-mcp

Use hybrid search:

codex mcp add fortran-mcp --env FORTRAN_MCP_SEARCH_PROVIDER=hybrid -- fortran-mcp

</details> <details> <summary>OpenCode</summary>

Use lexical search (default):

opencode mcp add fortran-mcp --global -- fortran-mcp

Use semantic search:

opencode mcp add fortran-mcp --global --env FORTRAN_MCP_SEARCH_PROVIDER=semantic -- fortran-mcp

Use hybrid search:

opencode mcp add fortran-mcp --global --env FORTRAN_MCP_SEARCH_PROVIDER=hybrid -- fortran-mcp

</details>

Command reference

| Command | Description | | ------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------- | | fortran-mcp | Start the stdio MCP server. | | fortran-mcp serve | Start the HTTP server (--host, --port, --path, --allowed-host). | | fortran-mcp doctor | Show configuration and installed data. Use --json for machine-readable output. | | fortran-mcp data install <package> | Download and install core or semantic from the release catalog or a local bundle (--catalog, --bundle, --data-dir). | | fortran-mcp data remove <package> | Remove an installed core or semantic package (--data-dir). | | fortran-mcp data verify | Verify installed data packages (--data-dir). | | fortran-mcp source list | List reviewed sources with versions and provenance. Use --json for machine-readable output. | | fortran-mcp source sync <source>... | Download reviewed sources and rebuild their chunks and lexical index. Accepts one or more source IDs or --all (--data-dir). |

Development

git clone https://github.com/minhqdao/fortran-mcp.git
cd fortran-mcp
uv sync
uv run fortran-mcp

See CONTRIBUTING.md for development and testing instructions.

Sources

Fortran MCP uses a curated collection of Fortran documentation, references, examples, and tools. Each source is pinned to a specific revision and included under its applicable license.

| Source | License | | --- | --- | | Fortran Package Manager documentation website | MIT | | Fortran Standard Library specifications and guides | MIT | | GNU Fortran Compiler manual | GFDL-1.3-or-later | | CMake documentation for Fortran projects | BSD-3-Clause | | Fortran-lang intrinsic procedures reference | MIT AND GFDL-1.2-or-later | | Fortran-lang quickstart tutorial | MIT | | Fortran-lang best practices | MIT | | Fortran-lang object-oriented programming guide | MIT | | Fortran-lang Fortran 95 language reference | CC-BY-SA-4.0 | | Fortran-lang build, link, and distribution guide | MIT | | Fortran-lang Python–Fortran Rosetta Stone | MIT | | Fortran-lang floating-point comparison guide | MIT | | OpenMP 6.0.1 Fortran examples | OpenMP-Examples | | Fortran-focused GNU Make 4.4.1 manual extracts | GFDL-1.3-or-later | | NumPy 2.5.2 F2PY user guide and reference | BSD-3-Clause | | Fypp 3.2 documentation | BSD-2-Clause | | Open MPI 5.0.10 Fortran routine reference | BSD-3-Clause-Open-MPI | | Fortitude 0.9.2 linter rules and usage reference | MIT | | Selected Codee Open Catalog Fortran safety and performance guidelines | Apache-2.0 | | Old programming idioms explained | MIT | | PRIMA behavior-preserving Fortran modernization case study | BSD-3-Clause | | Beliavsky list of fpm-compatible Fortran projects | MIT | | Fortran-lang package index additions | MIT |

New sources should address gaps in coverage or improve retrieval quality on realistic benchmark questions. They must be legally redistributable and justify their storage costs and impact on search results.

Public availability alone does not grant redistribution rights, particularly for standards, books, and vendor manuals.

License

The server software is licensed under the MIT License.

Documentation sources retain their original copyrights and licenses; see docs/licenses/.