v2.6.0

Bun is now a first-class, CI-tested runtime, and the MCP server can serve streamable HTTP. The package has always declared engines.bun, but nothing proved the server actually booted under Bun — or under Node, for that matter. This release pins both: the server and CLI run under Bun ≥ 1.1 or Node ≥ 22, importing dist/mcp.js / dist/cli.js as libraries is now silent (no server start, no CLI usage dump), and under Bun the same mcp.js entry can serve the full MCP surface over loopback HTTP with --transport streamable-http for hosts that launch it as an HTTP service instead of a stdio child.

Added

• --transport streamable-http (Bun only). mcp.js accepts --transport <stdio|streamable-http> (default stdio, byte-identical behavior to previous releases), plus --port (default 3000; 0 picks an OS port, announced on the stderr listening line) and --host (default 127.0.0.1). The HTTP path is built on the MCP SDK 2.0's Web-standard createMcpHandler behind the same buildServer() factory stdio uses, so both transports can never drift apart; loopback host-header and origin validation are enforced in front of it. Launched under Node with --transport streamable-http, the server fails fast with a clear stderr message rather than half-serving. The listening URL goes to stderr only — stdout remains the stdio JSON-RPC channel. (src/mcp.ts)
• CI runtime job that gates the badge. Boots the BUILT dist/mcp.js under both node (22, matching the engines.node floor) and bun on every push/PR: silent-import checks for dist/mcp.js and dist/cli.js under both runtimes, a hand-rolled stdio JSON-RPC initialize + tools/list handshake under both runtimes (no SDK client, so the wire is what's asserted), and a streamable-http initialize round-trip under Bun. No browser involved, so every failure is a real regression. New bun run test:runtime runs the same suite locally (test/runtime-entry.test.ts, 7 tests). (.github/workflows/ci.yml)

Fixed

• Importing the entries is now silent under both runtimes. dist/mcp.js and dist/cli.js used to start serving / print usage the moment any bundler or require.resolve-style host imported them. Both files now gate on a direct-run check (realpathSync(process.argv[1]) against import.meta.url, which handles bin symlinks under npm/bunx and works identically under Node and Bun, ESM-only): only direct/bin invocation runs the server or CLI; library import is side-effect free. buildServer is exported from src/mcp.ts for embedders. (src/mcp.ts, src/cli.ts)