marfrit
175244ab89
From @deus, bundle sha256 f38898d3…, verified byte-identical on arrival; lmcp.lua sha256 57fb2413…, the checksum quoted in the handover. Only lmcp.lua changes; versions.lua and envelope.lua are byte-identical to what is already on this branch. luac -p passes on all three. What the three fixes do, checked in the file rather than taken on trust — the conformance suites are HTTP-only and structurally cannot see finding 1: #1 handle_request now DERIVES _legacy when it arrives unset, instead of relying on the HTTP transport to have pre-set it. Previously req._legacy was written in exactly one place (_dispatch_post) and read in three, and run_stdio calls handle_request directly — so on stdio initialize, ping and logging/setLevel fell through to -32601 Method not found. That is the first message any client sends, and it worked unconditionally on master. #6 An empty protocol version now counts as "none announced" rather than as an unknown one. Router and versions.check had disagreed: check("") returns true by rule a, while the router excluded "" from the legacy set and sent it down the new path to be rejected by the envelope. #4 Legacy replies go through jsonrpc_result_legacy, which does NOT inject resultType. The claim that these methods "keep the old shape" was not true on the wire before: legacy ping answered {"resultType":"complete"} where master answered {}. Still open from the same review, deliberately not in this commit: #2 (the server-initiated SSE machinery is unreachable — nothing sets sess.sse_conn since the GET branch was removed), #3 (GET/DELETE answer 405 to legacy clients too, because _legacy is consulted at method dispatch and not at HTTP verb routing), #5 (routing accepts a header-only or _meta-only announcement, envelope.check then demands both), #7 (-32021 mapped but never produced, -32600 unmapped). Still NOT on master.
lmcp — Lua MCP server
Lightweight Model Context Protocol (MCP) server in pure Lua.
Runtime dependencies
- Lua 5.1+
- luasocket — needed for the TCP
listener. Packaged as
lua-socketon Arch/ALARM,lua-socketon Debian.
Files
| File | Role |
|---|---|
lmcp.lua |
library: protocol handling, tool registration |
server.lua |
HTTP server loop |
json.lua |
vendored JSON encoder/decoder |
example_server.lua |
sample server with a couple of tools |
Install
Packaged as lmcp in the marfrit overlay repo:
# Arch / ALARM
sudo pacman -S lmcp
# Debian
sudo apt install lmcp
Files land under /usr/share/lua/5.4/ (Lua LUA_PATH).
The example server installs as /usr/bin/lmcp-example.