VS Code FetchSandbox verify_behavior
How to: VS Code FetchSandbox verify_behavior
Add FetchSandbox to VS Code
-
01
Open .vscode/mcp.json and merge this in. Keep any servers already there.
{
"servers": {
"mcp": {
"type": "http",
"url": "https://fetchsandbox.com/mcp/v1"
}
}
}-
02
Save the file and restart VS Code.
-
03
Ask for something verify_behavior does. VS Code lists the server's tools on connect and calls verify_behavior itself — you do not invoke it by name.
-
04
If nothing happens, check the server is running and that FetchSandbox's identifier in your config matches the one above exactly.
Requires agent mode. MCP: Open User Configuration puts the same block in every workspace. VS Code docs
Set these first
FetchSandbox will not start until these are set, so verify_behavior never becomes available.
-
FETCHSANDBOX_API_KEY -
FETCHSANDBOX_TELEMETRY -
FETCHSANDBOX_BASE_URL
Same tool, other clients
This list was read from the server itself, by connecting to it and calling tools/list on 24 September 2026. It is what
the server actually exposes, not what its listing claims.
Mutating and Read-only are read off each tool's name, not its schema — a hint, not a guarantee. The registry stores tool names only; connect the server for its live schemas.