Ffl MCP Server

Backed by [ffl](https://github.com/nuwainfo/ffl), which turns any file/folder into an HTTPS link.

Local serverstdioPython

What is the Ffl MCP MCP server?

If you already use Ffl MCP, the ffl mcp mcp server is the piece that lets your assistant work with it directly. Backed by ffl, which turns any file/folder into an HTTPS link.

Available tools

The toolset is worth reading before you wire it up, because it tells you what the integration is really for:

  • Sharing — Preview sidecar routes (/manifest, /file, /thumb) are only created for folder shares and multi-file shares. Single-file shares are served as direct
  • Downloading — Downloads from FastFileLink URLs (WebRTC P2P when possible, HTTP fallback) or any HTTP(S) URL (works like wget)
  • Keygen — Generates an RSA keypair for passwordless pubkey recipient auth: - .fflpub — share with the sender (pass as recipientPublicKey) - .fflkey

Installation

Setup follows the usual MCP pattern — install or clone the server, register it in your client's configuration file, restart the client. The configuration blocks on this page cover the common clients.

Credentials and setup notes

Configuration is passed through the environment: ALLOWED_BASE_DIR, FFL_USE_STDIN, FFL_BIN, FFL_CORE_PATH. Treat anything key-shaped as a real credential — scope it to the minimum the server needs, and rotate it if it ever lands in a shared config.

Where it fits

Among the developer tooling options, the useful question is rarely "what can it do" but "what does it cost you to run" — permissions, credentials, and how much of your context its toolset consumes. Ffl MCP's toolset — Sharing, Downloading, Keygen — is a fair guide to whether it matches your workflow. It is maintained by nuwainfo; worth a glance at recent repository activity before you build anything load-bearing on it.

SyncDev reviews every entry in this directory against the project's own documentation before publishing, and revisits them as servers change.

Worth knowing first

  • It runs with your machine's permissions. That is convenient and also the reason to think about what you point it at before you approve a tool call.
  • Keep per-call confirmation enabled while you learn its behaviour; it is the cheapest safeguard you have.

Available tools

ToolWhat it does
SharingPreview sidecar routes (/manifest, /file, /thumb) are only created for folder shares and multi-file shares. Single-file shares are served as direct file links, even when preview=True. MCP returns the base FastFileLink UR
DownloadingDownloads from FastFileLink URLs (WebRTC P2P when possible, HTTP fallback) or any HTTP(S) URL (works like wget).
KeygenGenerates an RSA keypair for passwordless pubkey recipient auth: - <name>.fflpub — share with the sender (pass as recipientPublicKey) - <name>.fflkey — keep private (pass as recipientPrivateKey when downloading)

How to install the Ffl MCP MCP server

---

## MCP Config (manual JSON)

```json
{
  "mcpServers": {
    "ffl": {
      "command": "uvx",
      "args": ["--from", "git+https://github.com/nuwainfo/ffl-mcp", "ffl-mcp"],
      "env": {
        "ALLOWED_BASE_DIR": "/Users/you/Downloads",
        "FFL_USE_STDIN": "1"
      }
    }
  }
}

Configuration as documented by the project. Restart the client after saving.

Configuration

VariableDescriptionRequired
ALLOWED_BASE_DIRFilesystem location the server is allowed to use.Optional
FFL_USE_STDINConfiguration value read at startup.Optional
FFL_BINConfiguration value read at startup.Optional
FFL_CORE_PATHFilesystem location the server is allowed to use.Optional

Example prompts to try

  • Use Ffl MCP to Sharing.
  • Use Ffl MCP to Downloading.
  • Use Ffl MCP to Keygen.

Frequently asked questions

It connects Ffl MCP to MCP-compatible AI assistants such as Claude and Cursor, exposing 3 tools (Sharing, Downloading, Keygen) that the assistant can call on your behalf. Instead of copying data back and forth by hand, the assistant works with Ffl MCP directly.