Patchloom — Claude Code MCP server: what it does, how to install
Structured editing tool for JSON, YAML, TOML, and Markdown files that keeps formatting intact. Helpful when an agent must apply multi-file updates in a single turn.
claude mcp add patchloom -- npx -y patchloomWhat Patchloom does
Standard filesystem servers treat documents as raw text strings. That approach frequently leads LLMs to corrupt indentation in YAML files or drop trailing commas in JSON. Patchloom uses structured parsers instead. It updates entries through target selectors, leaving comments and formatting intact.
The server supports multi-file grouping with batch and tx operations. Instead of waiting through multiple LLM round-trips, an agent issues one call to patch several files. If a check fails under strict settings, Patchloom reverts the entire transaction. It also provides AST modifications across 20 programming languages and edits Markdown tables relative to specific headings.
When running as an MCP server, path sandboxing remains permanently active to block directory traversal with ../ or absolute targets. Running it via npx requires an existing Node.js setup on your host system.
What it helps with
- modify YAML and TOML keys without erasing comments
- bundle multi-file edits into a single atomic transaction
- insert rows into Markdown tables by heading name
- rename code symbols using AST across 20 languages
- revert failed batch modifications automatically
Example prompts for the agent
- Update the database port to 5432 in config.yaml using patchloom.
- Bump the release version to 2.0.0 in package.json, config.toml, and README.md in one batch.
- Append a new row to the table under the API heading in README.md.
How to install Patchloom
Platform CLI
claude mcp add patchloom -- npx -y patchloomPlatform CLI
codex mcp add patchloom -- npx -y patchloomConfig file
{
"mcpServers": {
"patchloom": {
"command": "npx",
"args": [
"-y",
"patchloom"
]
}
}
}Config file
{
"servers": {
"patchloom": {
"type": "stdio",
"command": "npx",
"args": [
"-y",
"patchloom"
]
}
}
}Platform CLI
gemini mcp add patchloom npx -y patchloomStep by step, with commands for each platform: How to add an MCP server to Claude Code, Codex, Cursor, VS Code, Gemini CLI and more
Questions about Patchloom
How to install Patchloom in Claude Code?
Run claude mcp add patchloom -- npx -y patchloom in your terminal. This registers the server and exposes its editing tools to Claude Code.
How is Patchloom different from basic filesystem MCP tools?
Basic filesystem servers replace raw text lines. Patchloom parses documents into syntax trees to modify target values by path selector, preserving existing indentation and comments.
Does Patchloom prevent unauthorized directory access?
Yes. In MCP server mode, sandbox security stays on continuously. It rejects paths that attempt to climb out of the workspace using ../ or absolute file references.
