jDocMunch MCP

jDocMunch is an MCP server for coding agents that retrieves the exact documentation section a task needs, without loading whole files into the context window.

Index a documentation set once by heading hierarchy, then fetch a single section, a heading subtree, or a ranked search result — extracted byte-precisely from the original file.

Install · Quickstart · Benchmarks · Commercial licensing

Free for personal use. Commercial use requires a paid license — terms below.

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Why jDocMunch?

The problem. An agent asked "how do I configure authentication?" opens a documentation file, skims hundreds of paragraphs it does not need, opens another, and repeats. Large context windows do not fix this. They just make the waste affordable enough to ignore until the bill arrives, and they crowd out the context the model actually needed.

The mechanism. jDocMunch parses a documentation set into a section tree keyed by heading hierarchy, stores each section's byte offsets into the original file, and exposes retrieval over MCP. Sections keep durable identities across re-indexing as long as path, heading text, and heading level are unchanged.

The outcome. The unit of access changes from file to section. An agent retrieves the installation section, one configuration block, or a specific heading subtree — and nothing else.

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What makes it different

Section-first retrieval

Search and retrieve documentation by section, not just file path or keyword match.

Byte-precise extraction

Full content is pulled on demand from exact byte offsets into the original file.

Stable section IDs

Sections retain durable identities across re-indexing when path, heading text, and heading level remain unchanged.

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Evidence

Four benchmarks against public documentation corpora, each with the corpus, date, and per-query results recorded in benchmarks/.

Corpus	Scale	Indexed in	Result
Kubernetes (kubernetes/website, 2026-03-04)	1,569 .md files, 4,355 sections, 16 MB	3,352 ms	27,285 tokens saved on a single node-affinity query; 100 ms latency
SciPy	10,402 sections, ~855,000 corpus tokens	2,247 ms	135–152 ms per query across sparse-solver, FFT, and optimization lookups
LangChain (MDX)	5,973 sections	5,204 ms	MDX-aware sectioning found 754% more sections than the naive pass
Wiki	7,449-token corpus	—	Search returns ranked metadata in ~190 tokens against a 7,449-token whole-corpus read

Read these as per-corpus results, not as a single headline multiple. Savings depend on how large the containing file is relative to the section you needed: a small file with one heading saves almost nothing, and the Kubernetes corpus saves a great deal. The benchmark files record the queries that did poorly alongside the ones that did well.

A separate, measured result from the v1.121.0 projection work, on this repository's own docs at max_results=10: a search row went 1,989 chars → 319 with compact=true (−84%), or 431 with snippet_bytes=200 (−78%) while removing the follow-up get_section call entirely.