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ciresnaveMCP SERVER · OFFICIAL PROJECT

JSON MCP Server

Read, query, write and validate JSON files — including ones too big to paste.

by ciresnave ↗Spreadsheet & Tabular File Analysis✓ Official

LABSCO SUMMARY

The point is the files you cannot paste.

Pagination and streaming mean a multi-gigabyte JSON file is answerable one slice at a time, and a targeted JSONPath query filters before anything reaches the model's context. That is the whole argument for using this rather than reading the file into the conversation. The csv and markdown output formats on json-query are worth remembering — they turn a query result into something you can read directly rather than more JSON.

What it is

A JSON file server written in Rust. It reads files with JSONPath filtering and pagination, runs JSONPath queries with a choice of output formats, writes with several merge strategies, and validates syntax — all against files on disk rather than content pasted into the conversation.

What you get

  • json-read takes a file_path, an optional json_path filter, start_index and limit (default 1000), and an output_format of json, pretty or compact
  • json-query runs a JSONPath expression and can return json, pretty, compact, csv or markdown
  • json-write writes with a mode of replace, merge_shallow, merge_deep or append
  • json-validate checks structure and syntax and reports line and column where it can
  • json-help has a topic argument covering overview, tools, jsonpath, examples and troubleshooting
  • Full JSONPath support including recursive descent (..field) and filter expressions ([?(@.field > value)])
  • Large files stream rather than load, so memory use stays constant regardless of file size, and line-delimited JSON is detected automatically

Requirements

A single binary. cargo install json-mcp-server is the recommended route; there are also install scripts for Linux, macOS and Windows, pre-built release binaries, .deb and .rpm packages, and an AUR PKGBUILD. The client entry is just the json-mcp-server command with no arguments; it speaks JSON-RPC over stdin and stdout. No account, no key, no network. Verify with json-mcp-server --version.

Setup effort

One command — cargo install json-mcp-server

See installation options