FFF for VS Code
Workspace-scoped fff-mcp for Copilot Chat and other language-model clients in VS Code.
Why an extension?
Global / user-level MCP configs for fff-mcp often start with no project path, so the server falls back to the process working directory (frequently $HOME) and tries to index everything.
This extension registers fff-mcp through VS Code's mcpServerDefinitionProviders API and always passes the current workspace folder as the index root.
Requirements
- VS Code
1.125+ (or compatible)
- System-installed
fff-mcp on PATH (or configure fff.binaryPath)
Install fff-mcp (example):
curl -fsSL https://raw.githubusercontent.com/dmtrKovalenko/fff.nvim/main/install-mcp.sh | bash
What you get
Each open workspace folder becomes one MCP server labeled FFF (or FFF (<folder>) in multi-root workspaces). The server exposes the same tools as CLI fff-mcp:
| Tool |
Purpose |
grep |
Content search (default) |
find_files |
Fuzzy file-name search |
multi_grep |
OR search across multiple patterns |
Settings
| Setting |
Scope |
Default |
Description |
fff.enabled |
resource |
true |
Enable FFF MCP for this folder |
fff.binaryPath |
machine-overridable |
fff-mcp |
Path to the executable |
fff.extraArgs |
resource |
["--no-update-check"] |
Extra args after the workspace path |
fff.frecencyDb |
resource |
"" |
Optional --frecency-db |
fff.historyDb |
resource |
"" |
Optional --history-db |
fff.logFile |
resource |
"" |
Optional --log-file |
fff.logLevel |
resource |
"" |
Optional --log-level |
fff.maxCachedFiles |
resource |
null |
Optional --max-cached-files |
Example (user or workspace settings.json):
{
"fff.binaryPath": "/usr/bin/fff-mcp",
"fff.extraArgs": ["--no-update-check", "--no-warmup"],
"fff.maxCachedFiles": 20000
}
Commands
- FFF: Show MCP Server Status — print the resolved command/args/cwd for each provided server.
Development
npm install
npm run compile
# F5 → "Run Extension"
In the Extension Development Host:
- Open a project folder.
- Open Chat (agent mode) and confirm FFF tools appear.
- Optionally run FFF: Show MCP Server Status.
Notes
- Prefer this extension over a global
fff entry in user mcp.json for project work, so indexing stays on the workspace root.
- Multi-root workspaces get one
fff-mcp process per enabled folder.
- Child processes are spawned by VS Code (stdio MCP); the extension only supplies definitions.
