Add Bearer auth, rewrite example server, add README

- lmcp.lua: optional Bearer token auth via conf file or explicit token
- lmcp.lua: CORS Authorization header allowed
- example_server.lua: rewritten with non-blocking shell, file ops, search
- README.md: usage, auth config, Claude Code integration, tool examples

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

example_server.lua

@@ -1,73 +1,100 @@
 #!/usr/bin/env lua
--- Example lmcp server — shell tools
--- Usage: lua example_server.lua [port]
+-- Example lmcp server — customize tools for your host
+local dir = arg[0]:match("(.*/)")  or "./"
+package.path = package.path .. ";" .. dir .. "?.lua"
+local lmcp = require("lmcp")
 
-local dir = arg[0]:match('(.*/)')  or './'
-package.path = package.path .. ';' .. dir .. '?.lua'
-
-local lmcp = require('lmcp')
-
-local server = lmcp.new("example-tools", {
-    port = tonumber(arg[1]) or 8080,
+local server = lmcp.new("my-tools", {
+    port = tonumber(os.getenv("LMCP_PORT")) or 8080,
+    -- Optional: Bearer token auth from config file
+    -- conf = dir .. "lmcp.conf",
+    -- Or set directly:
+    -- auth_token = "my-secret-token",
 })
 
-server:tool("shell", "Execute a shell command", {
+-- Non-blocking shell execution with timeout
+local function run(cmd, timeout_sec)
+    timeout_sec = timeout_sec or 120
+    local base = os.tmpname()
+    local out_file = base .. ".out"
+    local done_file = base .. ".done"
+    local sh_cmd = string.format("(%s) > '%s' 2>&1; echo $? > '%s'", cmd, out_file, done_file)
+    os.execute("sh -c ' " .. sh_cmd .. " ' &")
+    local elapsed = 0
+    local interval = 50
+    while elapsed < timeout_sec * 1000 do
+        local f = io.open(done_file, "r")
+        if f then f:close(); break end
+        if interval < 1000 then
+            os.execute("sleep 0." .. string.format("%03d", interval))
+        else
+            os.execute("sleep " .. math.ceil(interval / 1000))
+        end
+        elapsed = elapsed + interval
+        if interval < 2000 then interval = math.floor(interval * 1.5) end
+    end
+    local f = io.open(out_file, "r")
+    local output = f and f:read("*a") or ""
+    if f then f:close() end
+    os.remove(out_file); os.remove(done_file); os.remove(base)
+    if elapsed >= timeout_sec * 1000 then return "Error: timed out after " .. timeout_sec .. "s" end
+    return output ~= "" and output or "(no output)"
+end
+
+-- Register tools
+server:tool("shell", "Execute a shell command.", {
     type = "object",
     properties = {
-        command = { type = "string", description = "Shell command to execute" },
-        timeout = { type = "integer", description = "Timeout in seconds", default = 30 },
+        command = { type = "string" },
+        cwd = { type = "string" },
+        timeout = { type = "integer", default = 120 },
     },
     required = { "command" },
-}, function(args)
-    local handle = io.popen(args.command .. ' 2>&1', 'r')
-    if not handle then return "Error: could not execute command" end
-    local result = handle:read('*a')
-    handle:close()
-    return result ~= '' and result or '(no output)'
+}, function(a)
+    local c = a.command
+    if a.cwd then c = "cd \"" .. a.cwd .. "\" && " .. c end
+    return run(c, a.timeout or 120)
 end)
 
-server:tool("read_file", "Read a file", {
+server:tool("read_file", "Read a file.", {
     type = "object",
-    properties = {
-        path = { type = "string", description = "File path to read" },
-    },
+    properties = { path = { type = "string" } },
     required = { "path" },
-}, function(args)
-    local f = io.open(args.path, 'r')
-    if not f then return "Error: could not open " .. args.path end
-    local content = f:read('*a')
-    f:close()
-    return content
+}, function(a)
+    local f = io.open(a.path, "r")
+    if not f then return "Error: could not read " .. a.path end
+    local c = f:read("*a"); f:close(); return c
 end)
 
-server:tool("write_file", "Write content to a file", {
+server:tool("write_file", "Write content to a file.", {
     type = "object",
-    properties = {
-        path = { type = "string", description = "File path to write" },
-        content = { type = "string", description = "Content to write" },
-    },
+    properties = { path = { type = "string" }, content = { type = "string" } },
     required = { "path", "content" },
-}, function(args)
-    local f = io.open(args.path, 'w')
-    if not f then return "Error: could not open " .. args.path .. " for writing" end
-    f:write(args.content)
-    f:close()
-    return string.format("Written %d bytes to %s", #args.content, args.path)
+}, function(a)
+    local f = io.open(a.path, "w")
+    if not f then return "Error: could not write " .. a.path end
+    f:write(a.content); f:close()
+    return string.format("Written %d bytes to %s", #a.content, a.path)
 end)
 
-server:tool("list_dir", "List directory contents", {
+server:tool("list_dir", "List directory contents.", {
+    type = "object",
+    properties = { path = { type = "string", default = "." } },
+}, function(a)
+    return run("ls -la '" .. (a.path or ".") .. "'", 10)
+end)
+
+server:tool("search_files", "Search for files by name.", {
     type = "object",
     properties = {
-        path = { type = "string", description = "Directory path", default = "." },
+        pattern = { type = "string" },
+        path = { type = "string", default = "/" },
+        max_depth = { type = "integer", default = 4 },
     },
-}, function(args)
-    local path = args.path or '.'
-    local handle = io.popen('ls -1 ' .. path:gsub("'", "'\\''") .. ' 2>&1')
-    if not handle then return "Error: could not list " .. path end
-    local result = handle:read('*a')
-    handle:close()
-    return result
+    required = { "pattern" },
+}, function(a)
+    return run(string.format("find '%s' -maxdepth %d -name '%s' 2>/dev/null",
+        a.path or "/", a.max_depth or 4, a.pattern), 30)
 end)
 
-io.stderr:write("Starting lmcp example server...\n")
 server:run()