VS Code k402 prove_preflight
How to: VS Code k402 prove_preflight
Add k402 to VS Code
-
01
Open .vscode/mcp.json and merge this in. Keep any servers already there.
{
"servers": {
"k402": {
"type": "http",
"url": "https://x402-compute.68cxgfyr0.workers.dev/mcp"
}
}
}-
02
Save the file and restart VS Code.
-
03
Ask for something prove_preflight does. VS Code lists the server's tools on connect and calls prove_preflight itself — you do not invoke it by name.
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04
If nothing happens, check the server is running and that k402'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
k402 will not start until these are set, so prove_preflight never becomes available.
-
K402_GATEWAY -
K402_SESSION
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.