claude -p with HTTP MCP server silently exits with no output

Description

claude -p with --mcp-config containing an HTTP MCP server silently exits with code 0 and produces no output. Local stdio MCPs work fine. This has persisted since at least 2.1.58 through current 2.1.71.

Reproduction

# Works fine — no MCP:
claude -p "say hello" --output-format json

# Works fine — stdio MCP:
claude -p "say hello" --mcp-config '{"mcpServers":{"pw":{"command":"npx","args":["@playwright/mcp@latest","--headless"]}}}' --output-format json

# Silent exit, code 0, no output — HTTP MCP:
claude -p "say hello" --mcp-config '{"mcpServers":{"notion":{"type":"http","url":"https://mcp.notion.com/mcp"}}}' --output-format json

# Also silent exit with any HTTP URL:
claude -p "say hello" --mcp-config '{"mcpServers":{"test":{"type":"http","url":"https://httpbin.org/status/200"}}}' --output-format json

Expected behavior

claude -p should either:

1. Connect to the HTTP MCP and proceed normally, OR
2. Fail with a clear error message if the connection fails

Actual behavior

Process exits with code 0, no stdout, no stderr. Completely silent.

Environment

• Claude Code: 2.1.71
• macOS 15.3 (Darwin 24.3.0), arm64
• Node: v22.20.0

Notes

• The old schema ("url":"..." without "type":"http") is now properly rejected with a schema validation error — that part was fixed
• The issue is specifically with the HTTP transport in -p (print/non-interactive) mode
• --strict-mcp-config vs without makes no difference
• This blocks using any remote/HTTP MCP server (Notion, GitHub, etc.) in headless/automated scripts