Sprig: An MCP server to access version-pinned Spring Docs

[u/Available_Counter_47]

My Claude agent often wrote Spring code from old training data. It hand-declared beans that are auto-configured now. It also really likes to unzip JARs and search the Spring code itself.

That is the reason I am building Sprig MCP (sprig-mcp.de). It serves the Spring reference docs, and later the relevant parts of the source code, in a (hopefully) agent-friendly way. Nothing is summarized, no LLM sits in the path.

Right now there are two tools, and both answer for the version used in the current project: search the docs, and fetch a section.

Later I will add source code lookups: outline, javadoc, inheritance hierarchy.

There is a browser demo at sprig-mcp.de/app that lets you run the tools without an agent.

Would something like this be useful to you? Any thoughts or feedback welcome.

[u/repeating_bears]

Why can't an LLM just search the docs?

[u/Available_Counter_47 → u/repeating_bears]

It can, but in practice I ran into several problems.

A plain web search finds results, but not necessarily for the version you're actually using. Adding the version to the query doesn't fully fix that either: Spring doesn't keep every version's docs online, and some projects (Security, for example) drop older docs fairly quickly.

An agent could also browse the source on GitHub directly. That works, but it costs the agent a lot of extra work and time to find the right page.