Open source · MIT

Structured reads and writes for Markdown.

Give AI agents a reliable way to work with the structure of your documents (a heading, a section, a list item) without brittle string manipulation, and leave every other byte exactly as it was. nodiom is an open-source TypeScript library and MCP server. It’s what Nodiom Cloud runs on, and it’s yours to use on its own.

nodiom on GitHub nodiom-mcp on GitHub

doc.write('## Tasks > li[contains="auth"]', …)

# Project Aurora ## Tasks - [ ] Add OAuth login- [x] Add OAuth loginchanged- [ ] Write the API docs- [x] Set up CI ## Notes Ship by Friday. Keep the old endpoints for a week.

1 node changed10 other lines byte-identical

The library

TypeScript

import { Nodiom } from '@synexiom-labs/nodiom';

const doc = await Nodiom.fromFile('./plan.md', { lock: true });

doc.read('## Tasks > li[contains="auth"]');     // one item, by its content
doc.append('## Tasks', '- [ ] Rotate signing keys');
doc.write('## Notes[1]', 'Replaces the second "Notes" section only.');

await doc.save(); // writes and releases the lock

The MCP server

Claude Code

$ claude mcp add -s user nodiom -- npx -y @synexiom-labs/nodiom-mcp

Gives a local agent the same structural tools — tree, read, write, append, delete — over files on your machine. Any MCP client can run it with npx -y @synexiom-labs/nodiom-mcp.

Every other byte stays put

An edit rewrites only the node it targets. Untouched sections are never re-serialised, so whitespace, tables and formatting survive exactly. In a sample of 2,369 real Markdown files, every one round-trips byte-identically.

It refuses to guess

A selector that could mean two things — a heading that appears twice, a content match that hits two items — is an error naming the options, never a silent edit to the first.

Frontmatter is left alone

YAML and TOML frontmatter parses as its own node: never a heading, never in a section’s scope, untouched by every edit.

Open source and Cloud

Structured state inside Markdown. Shared state across agents and people.

Use nodiom on its own for one agent on one machine. Move to Nodiom Cloud when several agents, and the people supervising them, need the same state: one board where work is handed in, reviewed and approved.

	nodiom (open source)	Nodiom Cloud
Where the Markdown lives	Files on your disk	A shared copy every agent can reach
Who can write	Processes on one machine, one at a time	Many agents, on any machine, at once
When two writes collide	A file lock makes the second wait	Writes queue in the database — none lost
Boards	The format: headings and checklists	Board tools, a live board, a review column
Who changed what	—	Every change tied to the agent’s key
Price	Free, MIT licence	Free tier · Pro $49/month