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feat(mcp): serve MCP over Streamable HTTP with of mcp --http - #55
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`of mcp` only spoke stdio, so agents on other machines couldn't reach it. `--http [port]` serves stateless Streamable HTTP at http://127.0.0.1:<port>/mcp (default 3939), building a fresh McpServer per request so concurrent clients stay isolated. It binds to loopback only and accepts loopback Host names plus any `--allow-host` names, compared as host[:port] authorities, so a local browser can't reach it through DNS rebinding while a proxy such as `tailscale serve` can. Paths are matched without URL parsing so a malformed request target can't throw, and at most 16 requests run at once, since tool calls finish even after a client disconnects. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
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Minor release: `of mcp --http` serves the MCP server over Streamable HTTP on loopback, with a Host allowlist for publishing it through a proxy such as `tailscale serve` (#55). Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
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of mcponly spoke stdio, so agents on other machines couldn't reach it.of mcp --http [port]serves stateless Streamable HTTP athttp://127.0.0.1:<port>/mcp(default 3939), building a freshMcpServerper request so concurrent clients stay isolated. Tool registration moves intocreateMcpServer()for that; the rest ofserver.tsis indentation.It binds to loopback only. The Host allowlist (loopback names plus
--allow-host) blocks DNS rebinding from local browsers while letting a reverse proxy through, so publishing it on a tailnet is:An adversarial Codex review found a request target like
POST //[crashed the process through a synchronousnew URL(); paths are now matched without URL parsing. It also flagged unbounded concurrent tool runs (now capped at 16 with 503 +Retry-After) and loose Host parsing (now stricthost[:port], normalized on both sides). Tool calls still run to completion if a client disconnects.Bun's HTTP server never reports a client that disconnects mid-request, so the cap test runs the built CLI under Node, the shipped runtime; it fails if the slot isn't released. The official MCP client completes initialize,
tools/list, and tool calls throughtailscale serve.🤖 Generated with Claude Code