MCP for AI assistants

LAN Share comes with a Model Context Protocol server. Add it to Claude, Codex, Cursor or any other MCP client, and the assistant can see your computers, check why one does not answer, and send files, folders and text in plain words, while the files still go straight across your network.

How it works#

An MCP server is a small program your assistant starts on your own computer and talks to over standard input and output. LAN Share's is the lanshare command itself: lanshare mcp. It offers the assistant a set of tools, the assistant decides when to call them, and LAN Share does the actual work, exactly as if you had clicked it in the app.

1. Your assistantClaude, Codex, Cursor, VS Code…
2. lanshare mcpon this computer, JSON-RPC over stdio
3. Your networkencrypted, direct, TCP 45821
4. The other computera person accepts the transfer

• Nothing goes through a server of ours. No account, no upload, no API key. The MCP server runs locally and sends directly to the other computer.
• The receiver stays in control. Every transfer is offered and must be accepted on the other side, unless that computer already trusts yours.
• Same settings as the app. The tools read and write the same hosts, groups, history and settings as the LAN Share window and the lanshare command.

Full and built-in mode#

There are two ways to connect. Most people use full mode. The built-in mode exists for the Mac App Store version, where it is the only one, and for anyone who wants the assistant on a short leash.

On a Mac with the DMG from lanshare.io, Settings → CLI and MCP has three choices: Off, Built-in and Full, with the exact command to paste for each; it starts in Full. In the App Store version the page is called AI assistants and has only Off and Built-in; it starts in Off, so pick Built-in. With Built-in, the page shows Waiting for an assistant or how many are connected.

The Mac App Store version has no lanshare command (App Store rules), so full mode needs the DMG from lanshare.io. Don't install both on one Mac; see editions.

Set up your assistant#

1. Find the command#

MCP clients start the server themselves, usually without your shell's PATH, so give them the absolute path:

The path has a space in it on macOS and Windows: keep the quotes in the commands below. On Windows, use the folder you unpacked the zip into; the examples assume %LOCALAPPDATA%\Programs\LAN Share, as the install guide suggests.

2. Add it to your client#

$ claude mcp add --scope user lanshare -- "/Applications/LAN Share.app/Contents/MacOS/lanshare-cli" mcp

$ claude mcp add --scope user lanshare -- "/Applications/LAN Share.app/Contents/MacOS/lanshare-mcp"

$ claude mcp add --scope user lanshare -- /usr/bin/lanshare mcp

$ claude mcp add --scope user lanshare -- "$env:LOCALAPPDATA\Programs\LAN Share\lanshare.exe" mcp

{
  "mcpServers": {
    "lanshare": {
      "command": "/Applications/LAN Share.app/Contents/MacOS/lanshare-cli",
      "args": ["mcp"]
    }
  }
}

{
  "mcpServers": {
    "lanshare": {
      "command": "/Applications/LAN Share.app/Contents/MacOS/lanshare-mcp"
    }
  }
}

{
  "mcpServers": {
    "lanshare": {
      "command": "C:\\Users\\you\\AppData\\Local\\Programs\\LAN Share\\lanshare.exe",
      "args": ["mcp"]
    }
  }
}

[mcp_servers.lanshare]
command = "/Applications/LAN Share.app/Contents/MacOS/lanshare-cli"
args = ["mcp"]
# a send waits for the receiver to accept, then for the transfer
tool_timeout_sec = 600

[mcp_servers.lanshare]
command = "/usr/bin/lanshare"
args = ["mcp"]
tool_timeout_sec = 600

[mcp_servers.lanshare]
command = 'C:\Users\you\AppData\Local\Programs\LAN Share\lanshare.exe'
args = ["mcp"]
tool_timeout_sec = 600

{
  "mcpServers": {
    "lanshare": {
      "command": "/usr/bin/lanshare",
      "args": ["mcp"]
    }
  }
}

{
  "servers": {
    "lanshare": {
      "type": "stdio",
      "command": "/Applications/LAN Share.app/Contents/MacOS/lanshare-cli",
      "args": ["mcp"]
    }
  }
}

$ printf '%s\n' \
  '{"jsonrpc":"2.0","id":1,"method":"initialize","params":{"protocolVersion":"2025-06-18"}}' \
  '{"jsonrpc":"2.0","id":2,"method":"tools/call","params":{"name":"check_host","arguments":{"target":"10.0.0.20"}}}' \
  | lanshare mcp

{"id":1,"jsonrpc":"2.0","result":{"capabilities":{"tools":{}},"instructions":"LAN Share sends folders and files directly to other computers on the local network. …","protocolVersion":"2025-06-18","serverInfo":{"name":"lanshare","version":"0.9.0"}}}
{"id":2,"jsonrpc":"2.0","result":{"content":[{"text":"{\n  \"address\": \"10.0.0.20\",\n  \"alt_addresses\": [],\n  \"name\": \"10.0.0.20\",\n  \"online\": true\n}","type":"text"}],"isError":false}}

3. Try it#

Ask something harmless first, such as Which of my LAN Share computers are online? The assistant should call list_hosts and answer with your saved hosts. Most clients ask your permission before the first call of each tool.

Tools: sending#

LAN Share offers 19 tools (12 in built-in mode). Every result is text, which the assistant reads: pretty-printed JSON, except remove_host and remove_group, which answer with a sentence. When something goes wrong the call still answers, with "isError": true and a plain-English message (Test server rejected the transfer), so the assistant can explain it or try something else. Tools that only look at things are marked readOnlyHint, which lets many clients run them without asking each time.

• Sending

  send
  send_text
  send_to_group
  web_share

• Hosts and network

  list_hosts
  check_host
  diagnose
  discover
  add_host
  update_host
  remove_host

• Groups

  list_groups
  add_group
  rename_group
  remove_group

• This computer

  status
  list_received
  history
  stats

A target is a saved host's name, id or address, or any host, IP or host:port (in built-in mode, saved hosts only). A saved host with extra addresses (say Wi-Fi, cable and VPN) is tried address by address, 1.5 seconds each, and the first that answers is used.

{
  "target": "Test server",
  "paths": ["/Users/you/Projects/app/build"],
  "exclude": ["node_modules", "*.map"],
  "message": "Build 214 for testing"
}

{
  "target": "Test server",
  "address": "10.0.0.20",
  "items": "build",
  "files": 1284,
  "bytes": 432013312,
  "size": "412.0 MiB",
  "compressed": true,
  "wire_bytes": 301209600,
  "skipped_bytes": 0,
  "seconds": 4.7
}

{ "target": "Anna's MacBook", "text": "https://staging.example.com/build/214" }

[
  { "target": "QA Mac mini", "ok": true, "sent": { "target": "QA Mac mini", "items": "release-notes.pdf", "files": 1, "size": "1.2 MiB", "…": "…" } },
  { "target": "QA Windows", "ok": false, "error": "QA Windows rejected the transfer" }
]

{ "paths": ["/Users/you/Documents/invoice-2026-10.pdf"], "minutes": 15 }

{
  "url": "http://192.168.1.31:51544/9f2c4e7a1b8d3f60c5e2a7b94d1f8e36/",
  "urls": ["http://192.168.1.31:51544/9f2c4e7a1b8d3f60c5e2a7b94d1f8e36/"],
  "port": 51544,
  "expires_in": 900,
  "items": [{ "name": "invoice-2026-10.pdf", "is_dir": false, "files": 1, "bytes": 184320 }]
}

Tools: hosts and network#

[
  {
    "id": 1793561079457943000,
    "name": "Test server",
    "address": "10.0.0.20",
    "alt_addresses": ["10.8.0.20"],
    "group": "Servers",
    "online": true,
    "fingerprint": "XYHX-HOSQ-JBXO-QLAF"
  },
  {
    "id": 1793398994740048000,
    "name": "Anna's MacBook",
    "address": "192.168.1.40",
    "alt_addresses": [],
    "group": null,
    "online": false
  }
]

{ "address": "10.8.0.20", "alt_addresses": ["10.8.0.20"], "name": "Test server", "online": true }

{
  "address": "192.168.1.50",
  "ok": false,
  "steps": [
    { "name": "resolve", "ok": true, "ms": 0.8, "detail": "192.168.1.50 resolves to 192.168.1.50:45821" },
    { "name": "tcp", "ok": false, "ms": 3004.5, "detail": "No answer from 192.168.1.50:45821 within 3 s: the computer is off, on another network, or a firewall blocks TCP port 45821" },
    { "name": "protocol", "ok": false, "ms": null, "detail": "Skipped: no connection" },
    { "name": "version", "ok": false, "ms": null, "detail": "Skipped: no connection" }
  ],
  "peer": null,
  "tried": [{ "address": "192.168.1.50", "ok": false, "ms": 3005.1 }]
}

{
  "address": "10.0.0.20",
  "ok": true,
  "steps": [
    { "name": "resolve", "ok": true, "ms": 0.1, "detail": "10.0.0.20 resolves to 10.0.0.20:45821" },
    { "name": "tcp", "ok": true, "ms": 4.2, "detail": "Connected to 10.0.0.20:45821" },
    { "name": "protocol", "ok": true, "ms": 21.0, "detail": "LAN Share answered as \"test-server\"; encrypted, key XYHX-HOSQ-JBXO-QLAF" },
    { "name": "version", "ok": true, "ms": null, "detail": "LAN Share 0.9.0 (protocol 1), features: zstd, resume, sync, text, info, pair, noise" }
  ],
  "peer": { "name": "test-server", "version": 1, "app_version": "0.9.0", "features": ["zstd", "resume", "sync", "text", "info", "pair", "noise"] },
  "tried": [{ "address": "10.0.0.20", "ok": true, "ms": 26.3 }]
}

[
  { "name": "meeting-room-pc", "ip": "192.168.1.57", "port": 45821 },
  { "name": "test-server", "ip": "10.0.0.20", "port": 45821, "alt": ["10.8.0.20"] }
]

{ "name": "Meeting room", "address": "192.168.1.57", "group": "Office" }

{ "id": 1793641469516678000, "label": "Meeting room", "address": "192.168.1.57", "group": 1793487035370877000 }

{ "host": "Test server", "address": "10.0.0.42", "alt_addresses": ["10.8.0.42"] }

Removed host Meeting room

Tools: groups#

[
  { "id": 1793487035370877000, "name": "Office", "hosts": 4 },
  { "id": 1793398981799906000, "name": "Servers", "hosts": 2 }
]

{ "id": 1793656800123456000, "name": "QA" }

Removed group QA (3 hosts now without a group)

Tools: this computer and history#

{
  "device_name": "studio-mac",
  "port": 45821,
  "receiving": true,
  "receive_dir": "/Users/you/Downloads/LAN Share",
  "config_file": "/Users/you/Library/Application Support/lan-share/config.json",
  "hosts": 6,
  "groups": 2
}

[
  { "name": "contract-draft.docx", "path": "/Users/you/Downloads/LAN Share/contract-draft.docx", "is_dir": false, "modified": 1793639740 },
  { "name": "photos-october", "path": "/Users/you/Downloads/LAN Share/photos-october", "is_dir": true, "modified": 1793611200 }
]

[
  {
    "id": 1793641469516678000,
    "time": 1793641469,
    "direction": "received",
    "kind": "files",
    "peer": "Anna's MacBook",
    "address": "192.168.1.40",
    "items": ["contract-draft.docx"],
    "paths": ["/Users/you/Downloads/LAN Share/contract-draft.docx"],
    "files": 1,
    "bytes": 48213,
    "wire_bytes": 31022,
    "compressed": true,
    "duration_ms": 41,
    "status": "done",
    "message": "Please check section 4",
    "encrypted": true,
    "fingerprint": "XKAZ-FSCH-PYZF-IYBO"
  }
]

{
  "days": 30,
  "totals": {
    "sent_bytes": 647901184, "received_bytes": 1053712384,
    "sent": 14, "received": 11, "failed": 1,
    "saved_bytes": 308346880,
    "average_speed": 9793248.6, "fastest_speed": 61202112.0
  },
  "by_host": [
    { "peer": "NAS", "sent": 612368384, "received": 0, "transfers": 9, "last": 1793639845 }
  ],
  "daily": [
    { "start": 1793570400, "sent": 3000112, "received": 933146526 }
  ]
}

Example prompts#

You talk to the assistant in plain words; it picks the tools. These are realistic conversations and the calls a capable assistant makes. Yours may take a slightly different route.

Safety and permissions#

Several independent layers decide what an assistant can do:

1. Your client asks you. MCP clients ask before running a tool, and let you allow tools for good. Allowing the readOnlyHint tools (list_hosts, check_host, diagnose, discover, status, list_received, history, stats, list_groups) is harmless; keep the sending tools on “ask”.
2. The receiver accepts. Every transfer is offered to a person, who sees the sender, the items, the size and the note, and accepts or declines. The exception is a computer that already trusts yours (paired, Always accept, or lanshare receive --yes). There is no MCP tool to trust a sender, pair or forget a key: those stay with you.
3. Keys are checked. If the other computer's key is not the remembered one, sending is refused, whoever asks.
4. Built-in mode narrows it down. Sending only from the folders you allowed (checked after following links and .., so a link cannot lead out of them), only to saved hosts, no changes to hosts or groups, no web page. The connection is a socket only your user can open.
5. Your organisation's policy. "disable": ["mcp"] makes lanshare mcp refuse to start; "phone" switches off web_share, "text" blocks send_text, "sync" sync sends; hosts and groups from the policy cannot be removed; receive rules still apply on every receiver. See For organisations.

Long transfers and progress#

• A send can take minutes. It waits up to 3 minutes for the receiver to accept, then for the transfer itself. Calls run in parallel, so the assistant can keep using other tools meanwhile.
• Progress. For send and send_to_group, when the client asks for progress (a progressToken in the call), LAN Share sends notifications/progress with bytes done and total and the message Sending to Test server. Other tools, send_text included, report no progress.
• Client time limits. Some clients give up on a tool call after a minute or so. In Codex set tool_timeout_sec (see setup); in Claude Code the MCP_TOOL_TIMEOUT environment variable sets it in milliseconds. If a client gave up, the transfer may still have finished: ask for the history.
• Ending the session lets transfers that are under way finish before the server exits; a web_share page stops with it.

Troubleshooting#

No LAN Share tools in the client

The path is wrong or not absolute, or the client was not restarted. Run the command from step 1 in a terminal with mcp after it: it should sit and wait (press Ctrl+C). Then try the hand test under Other.

Built-in: only a status tool

lanshare-mcp opens LAN Share if it is not running, but Settings → CLI and MCP → Built-in (App Store: Settings → AI assistants → Built-in) must be selected there; otherwise the client sees one stand-in status tool that says so. Select Built-in, then restart the MCP server in your client. The settings page shows Waiting for an assistant, the number connected, or the error in red.

“… is outside the folders allowed in LAN Share”

Built-in mode: add the folder under Settings → CLI and MCP (App Store: AI assistants) → Allowed folders (your home folder allows almost everything).

“"10.0.0.9" is not a saved host”

Built-in mode sends only to saved hosts. Save it in the app first.

“add_host is not available in LAN Share's built-in MCP”

Hosts and groups are changed in the app in built-in mode.

“Test server rejected the transfer”

The person declined, or did not answer within 3 minutes.

“sending to … failed: … connection timed out”

The computer is off, elsewhere, or a firewall blocks TCP 45821. Ask the assistant to run diagnose.

The call timed out in the client

Raise the client's tool time limit (above), then check the history: it may have gone through.

“AI assistants (MCP) are switched off by your organisation's policy”

Your administrator disabled AI assistants (MCP) for this computer with "disable": ["mcp"]; lanshare mcp refuses to start and says so.

Still stuck? Support has the network checklist, or write to us with what lanshare diagnose <host> says.

Something missing or wrong? Write to [email protected].