MCP Server for Claude Desktop — Search Your Local Files

Workflows

What people do with it

Three workflow patterns where searching local files inside a Claude conversation collapses hours of work into minutes.

For compliance officers and audit teams

The pain. Pulling together every email, KYC update, and flagged transaction tied to a single customer takes four to six hours per case. The information lives across SharePoint exports, your local archive of past investigation files, and folders that — for regulatory reasons — cannot leave the building.

The setup. Point LocalSynapse at your compliance archive and your case folders. Add LocalSynapse to your Claude Desktop config. Nothing leaves the machine. Required by retention policy and consistent with most audit standards.

What it looks like.

Claude Desktop

Summarize all communications, KYC updates, and flagged transactions for customer 7842 between January and December 2024. Cite the source file for each item.

Found 12 communications, 3 KYC updates, and 5 flagged transactions for customer 7842. Structured summary with citations below.

case_7842_2024Q1.emlkyc_review_2024.pdftxn_flagged_log.xlsx

Claude calls LocalSynapse over MCP, retrieves the relevant snippets from the indexed corpus, and produces a structured summary with citations back to the original files. You verify against the source files, which are linked inline. Twenty minutes per case instead of four hours.

4 hours20 min

For technical writers and product managers

The pain. Your product has shipped a dozen versions across three years. When a customer asks "did the authentication flow change between v3.2 and v3.4?" the answer is buried across release notes, deprecated docs, internal RFC documents, and a few Confluence pages everyone forgot about.

The setup. Index your documentation repository, your release notes archive, and an exported dump of Confluence or Notion. Add LocalSynapse to Claude Desktop, Claude Code, or Cursor — same MCP server, any client.

What it looks like.

Claude Desktop

Show me every place we describe the authentication flow, grouped by product version. Highlight what changed between v3.2 and v3.4.

8 passages describe the authentication flow across v3.0 → v3.4. Key diff between v3.2 and v3.4: token rotation moved from refresh-on-use to fixed-window.

release_v3.4.mdrfc_042_auth.mdconfluence_auth_dump.html

Claude pulls the relevant passages, organizes them by version, and surfaces the diff in prose. Half a day of doc archaeology becomes five minutes of focused review.

half a day5 min

For independent consultants and solo practitioners

The pain. Three years of proposals, scoping docs, slide decks, and final reports — across roughly thirty clients. When a new lead asks "have you worked on something similar?" you spend two hours guessing filenames and opening folders, hoping to find the right precedent.

The setup. Point LocalSynapse at your entire client archive. Add it to Claude Desktop.

What it looks like.

Claude Desktop

Find the three past projects most similar to a B2B SaaS supply-chain optimization engagement. Pull the most relevant slide from each, with the file path.

Three closest matches to a B2B SaaS supply-chain engagement. Most relevant slide pulled from each, with file paths.

Acme_SCM_Proposal_2023.pdfsupply_chain_phase1.pptxlogistics_final_q3.docx

Claude searches semantically across decks and proposals, surfaces the closest matches, and quotes the relevant passages with file paths. Five minutes. The new pitch starts from real precedent, not a blank deck.

2 hours5 min

Setup

30-second setup

Three steps. No login. No cloud account. No telemetry.

1
Install LocalSynapse
Download the installer for Windows or macOS. Run it. Choose the folders you want indexed.
Download →
2
Add LocalSynapse to your Claude Desktop config
Open your Claude Desktop config file and add this entry under mcpServers:
```
{
  "mcpServers": {
    "localsynapse": {
      "command": "C:\\Program Files\\LocalSynapse\\LocalSynapse.exe",
      "args": ["mcp"]
    }
  }
}
```
Config file location:
Windows: %APPDATA%\Claude\claude_desktop_config.json
macOS: ~/Library/Application Support/Claude/claude_desktop_config.json
3
Restart Claude Desktop
Quit Claude Desktop completely and reopen it. LocalSynapse will appear in the MCP server list. You're ready.

Tools

What LocalSynapse exposes over MCP

Four tools, designed to be composable. Any MCP client can call them.

search_files

Search across the indexed corpus using keywords or natural-language queries. Returns ranked snippets with source file paths. Handles phrase queries, semantic queries, and BM25 + dense hybrid ranking.

get_file_content

Retrieve the full text of a specific indexed file by document ID. Useful when the snippets are not enough and the client needs the whole document.

list_indexed_files

Browse the corpus with filters by format or folder. Useful for orientation queries like "what audit documents do we have indexed?"

get_pipeline_status

Check the current state of indexing — scan progress, indexing progress, and embedding status. Useful for verifying coverage before relying on results.

Built on the official MCP C# SDK. All tools work with any MCP-compatible client.

Compatibility

Works with

Claude Desktop

Primary integration. The setup snippet above is for Claude Desktop.

Claude Code

Anthropic's terminal coding agent. Same MCP server, same config pattern.

Cursor

Code editor with native MCP support.

Cline

VS Code extension with MCP support.

Any MCP client

MCP is an open protocol. LocalSynapse works with any client that speaks it.

Don't see your client? If it speaks MCP, it works. Open an issue →

Privacy

What stays on your machine

The whole point.

All indexing is local.

Embeddings run on your CPU or GPU through ONNX Runtime. The model is downloaded once at first run and used offline thereafter.

The MCP server uses stdio.

LocalSynapse does not open a network port. Claude Desktop launches it as a child process and talks to it over standard input and output. No HTTP, no socket, no daemon.

Free tier sends no data.

A small anonymous version ping is sent only on user-initiated update check. Every other byte stays put. See the full disclosure.

Give Claude Desktop a local memory.

What people do with it

30-second setup

Install LocalSynapse

Add LocalSynapse to your Claude Desktop config

Restart Claude Desktop

What LocalSynapse exposes over MCP

Works with

Claude Desktop

Claude Code

Cursor

Cline

Any MCP client

What stays on your machine

All indexing is local.

The MCP server uses stdio.

Free tier sends no data.

Start searching with Claude.

Give Your AI Agent a Local Memory: MCP Server for File Search