Introducing the Mélodium MCP server

Mélodium 0.10.3 ships a new crate, melodium-mcp: an MCP  server that exposes Mélodium program validation and standard library reference lookup directly to MCP-compatible clients, including Claude, Cursor, Codex, Mistral, ChatGPT, and any other client implementing the protocol.

The point is straightforward: an AI agent writing Mélodium code should not have to guess at the standard library or wait for a human to run melodium check. It can call the same validation the CLI uses, on every attempt, and read the same reference documentation a human would.

What it links to

melodium-mcp links the melodium crate directly and reuses the exact loading functions the melodium check and melodium info CLI commands call, so an agent gets the same answers a human would from the terminal. Every standard library package is compiled in mock mode: validating a program never touches the filesystem, network, subprocesses, or a database beyond reading the file being checked.

The tools

• check_program: parse and validate a .mel, Compo.toml, or .jeu file, returning structured errors and the list of available entrypoints.
• get_program_info: describe each entrypoint of a program: identifier, documentation, and parameters.
• list_library_elements: list standard library treatments, functions, models, contexts, and data types, filterable by area (std/flow, http, …) and kind.
• describe_element: the full signature of one standard library element: documentation, generics, parameters, and (for treatments) inputs, outputs, required models and contexts.
• search_reference: keyword search across the standard library’s identifiers and documentation.
• get_language_guide: an explanation of Mélodium’s dataflow execution model (treatments, tracks, models, contexts, connections, generics, project layout), written for an AI reading or writing Mélodium code.
• get_cicd_migration_guide: a reference for migrating a GitHub Actions or GitLab CI pipeline to the cicd package.
• search_book and read_book_chapter: keyword search and full content of the Mélodium book ’s chapters.

The language guide, the CI/CD migration guide, and the book are all embedded into the binary at compile time. No network access is needed at runtime, and it’s the same reference material shipped as the melodium Claude Code skill.

Using it

Install it from the MCP registry  as tech.melodium/melodium-mcp, through any MCP client that supports it, or directly with Cargo:

cargo install melodium-mcp

Either way, point your MCP client at the resulting binary over stdio.