target %q looks like a remote MCP URL, but transport is %q.

Error message

target %q looks like a remote MCP URL, but transport is %q. Use --transport http or --transport sse

What it means

When transport is stdio (the default) but the target parses as an http/https URL with a host — looksLikeRemoteURL, helpers.go:259-273 — the CLI refuses to store a URL as a stdio command and names the fix (add.go:225-231). This catches the most common mistake: supplying a remote MCP URL while forgetting that transport defaults to stdio.

Source

Thrown at cmd/picoclaw/internal/mcp/add.go:226

		}
		if len(args) > 0 {
			return config.MCPServerConfig{}, fmt.Errorf("%s transport does not accept command arguments", transport)
		}
		parsedURL, err := url.ParseRequestURI(target)
		if err != nil || parsedURL.Scheme == "" || parsedURL.Host == "" {
			return config.MCPServerConfig{}, fmt.Errorf("invalid MCP URL %q", target)
		}
		server.URL = target
		server.Headers = headers
		return server, nil
	}

	if len(headers) > 0 {
		return config.MCPServerConfig{}, fmt.Errorf("--header can only be used with http or sse transport")
	}

	if looksLikeRemoteURL(target) {
		return config.MCPServerConfig{}, fmt.Errorf(
			"target %q looks like a remote MCP URL, but transport is %q. Use --transport http or --transport sse",
			target,
			transport,
		)
	}

	command := target
	commandArgs := append([]string(nil), args...)

	if err := validateLocalCommandPath(target); err != nil {
		return config.MCPServerConfig{}, err
	}
	if isLocalCommandPath(command) {
		command = expandHomePath(command)
	}

	server.Command = command
	server.Args = commandArgs

View on GitHub (pinned to 49183d7e8d)

Solutions

Append --transport http (streamable-http is accepted and normalizes to http)
Use --transport sse if the endpoint is a legacy SSE server
If you truly meant stdio, replace the URL with a local command path

Example fix

# before
picoclaw mcp add github https://api.githubcopilot.com/mcp/
# after
picoclaw mcp add github https://api.githubcopilot.com/mcp/ --transport http

Defensive patterns

Strategy: validation

Validate before calling

func looksLikeRemoteURL(target string) bool {
	u, err := url.ParseRequestURI(target)
	return err == nil && u.Host != "" &&
		(strings.ToLower(u.Scheme) == "http" || strings.ToLower(u.Scheme) == "https")
}

if looksLikeRemoteURL(target) && transport == "stdio" {
	transport = "http" // or fail loudly with a clear message
}

Prevention

Whenever the target starts with http:// or https://, always pass --transport http (or sse)
Pin the transport explicitly in scripts instead of relying on the stdio default

When it happens

Trigger: `picoclaw mcp add github https://api.githubcopilot.com/mcp/` with no --transport flag; `-t stdio` passed explicitly together with a URL.

Common situations: Following vendor MCP docs that show only a URL; coming from other CLIs that infer transport from the URL shape; copy-pasting an sse endpoint into a stdio-style command line.

Related errors

AI-assisted analysis of sipeed/picoclaw@49183d7e8d (2026-08-15). Data as JSON: /api/errors/379f50f9530e46ce. Report an issue: GitHub.