Haskell Hackage MCP

Hackage Documentation MCP

The Hackage Documentation MCP bridges a critical knowledge gap for AI assistants that need to work with Haskell. While many large language models excel at mainstream languages, their training data often underrepresents Haskell’s unique type system and library ecosystem. This results in inaccurate code generation, vague explanations, and a general lack of confidence when the model discusses Haskell modules. By exposing an MCP endpoint that pulls real‑time documentation from the official Hackage repository, the server equips assistants with authoritative references, dramatically improving both correctness and trustworthiness.

At its core, the MCP offers a single tool——that retrieves clean, text‑based documentation for any Haskell module in any published package. Developers can specify the exact package name and version, ensuring that the assistant references the precise API surface the user is working with. The output is formatted for easy ingestion: plain text that can be embedded directly into the assistant’s response, allowing the model to quote signatures, type constraints, and usage examples verbatim.

Key capabilities include:

• Version precision: Pin down documentation to a specific release, preventing mismatches caused by API changes across versions.
• Module granularity: Fetch documentation for individual modules, rather than entire packages, reducing noise and focusing the assistant’s explanations.
• Real‑time freshness: Each request pulls the latest published docs, so developers always see up‑to‑date information without manual updates.

Typical use cases span the entire Haskell development lifecycle. A novice learning a library can ask the assistant for the documentation of and receive an instant, accurate summary. A seasoned developer can verify that a generated function signature matches the official definition before integrating it into production code. Teams can automate documentation checks in CI pipelines by querying the MCP to confirm that generated helper functions conform to library contracts.

Integrating this server into existing AI workflows is straightforward. Any assistant that supports the MCP protocol can invoke via standard JSON messages, whether running locally or in a cloud environment. The server’s lightweight implementation (Python 3.7+, , , and ) means it can be deployed as a sidecar or embedded in a larger toolchain without significant overhead.

What sets this MCP apart is its focus on authoritative source material and version control. Unlike generic web scrapers or static documentation bundles, it pulls directly from Hackage’s published pages and respects the exact package version requested. This guarantees that the assistant’s references are both accurate and current, reducing hallucinations and boosting confidence in Haskell‑centric conversations.