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drunnellsMCP SERVER · OFFICIAL PROJECT

Pulsar Edit MCP Server

Let an assistant read and edit the file open in the Pulsar editor — targeted replacements, line operations, and the surrounding context for each match.

by drunnells ↗Editors, Terminals & Local Dev Environment✓ Official

LABSCO SUMMARY

Editing where the cursor is, not where the file is.

Operating on the open buffer rather than on disk is the distinction that matters: the assistant sees the selection, the undo stack is the editor's own, and a bad edit is one keystroke from being reversed. The context-around-match call is the thoughtful bit — it lets an edit be made against the code that surrounds it rather than a blind string replace. Treat the experimental warning as real.

What it is

A package for the Pulsar editor that turns the running editor into an MCP server. Instead of an assistant working on files through the filesystem, it operates on the active document in the editor — reading the selection, replacing text in place, and opening other project files into tabs. Pulsar's own chat panel or an external client such as AnythingLLM can drive it.

What you get

  • Targeted editing: replace a search string with a replacement, replace the whole document, or insert a block of text at a given line number
  • Context before you edit: return the lines before and after the Nth match of a query, so an edit is made with the surrounding code in view
  • Finding text: search the active editor with a substring or a regular expression and get the position of each occurrence, capped by a maximum match count
  • Line operations: insert a blank line at a row, delete a single line, or delete a range
  • Reading state: get the selection, the whole document as numbered lines, the line count, the filename and the full path
  • Project-level moves: list all project files, open one (or switch to its tab if it is already open), and undo or redo the last change

Requirements

Pulsar, with the package installed via ppm install https://github.com/drunnells/pulsar-edit-mcp-server and the server switched on under Packages → MCP Server → Listen — an "MCP:On" tile appears in the lower left when it is running. Third-party clients connect over streamable HTTP at http://localhost:3000/mcp. The author describes it as very experimental and incomplete.

Setup effort

One command — ppm install https://github.com/drunnells/pulsar-edit-mcp-server

See installation options