feat: resolves CWD variable in MCP server configs

Author: ravitemer

.mcphub/servers.json

@@ -4,7 +4,7 @@
       "args": [
         "-y",
         "@modelcontextprotocol/server-filesystem",
-        "${PWD}"
+        "${CWD}"
       ],
       "command": "npx"
     },
@@ -21,7 +21,7 @@
     "lsp": {
       "args": [
         "--workspace",
-        "${PWD}",
+        "${CWD}",
         "--lsp",
         "lua-language-server",
         "--",

doc/workspace.md

@@ -16,7 +16,7 @@ Consider these common scenarios:
   "mcpServers": {
     "filesystem": {
       "command": "uvx",
-      "args": ["mcp-server-filesystem", "${PWD}"]
+      "args": ["mcp-server-filesystem", "${CWD}"]
     }
   }
 }
@@ -29,7 +29,7 @@ Consider these common scenarios:
     "lsp": {
       "command": "mcp-language-server", 
       "args": [
-        "--workspace", "${PWD}",
+        "--workspace", "${CWD}",
         "--lsp", "typescript-language-server",
         "--", "--stdio"
       ]
@@ -40,6 +40,7 @@ Consider these common scenarios:
 
 Without workspaces, you'd need to manually edit the global config for every project. With workspaces, each project gets its own configuration automatically.
 
+
 ## How It Works
 
 #### 1. Project Detection
@@ -102,12 +103,12 @@ require("mcphub").setup({
   "mcpServers": {
     "filesystem": {
       "command": "uvx", 
-      "args": ["mcp-server-filesystem", "${PWD}"]
+      "args": ["mcp-server-filesystem", "${CWD}"]
     },
     "lsp": {
       "command": "mcp-language-server",
       "args": [
-        "--workspace", "${PWD}",
+        "--workspace", "${CWD}",
         "--lsp", "lua-language-server", 
         "--", "--stdio"
       ]
@@ -118,18 +119,19 @@ require("mcphub").setup({
 
 #### Environment Variables
 
-Variables like `${PWD}` are automatically available since the hub starts with the project directory as its working directory. Basic environment variables (`HOME`, `USER`, `TERM`, `SHELL`, etc.) are always available.
+`CWD` will be set to the working directory of the current running `mcp-hub`. Basic environment variables (`HOME`, `USER`, `TERM`, `SHELL`, etc.) are always available.
 
 Additional variables can be set via:
 1. **global_env** configuration in MCP Hub setup
 2. **Process environment** when the hub starts
 
 ```lua
 require("mcphub").setup({
-  global_env = {
-    "CUSTOM_VAR", -- Uses $CUSTOM_VAR from the environment
-    "DBUS_SESSION_BUS_ADDRESS" = os.getenv("DBUS_SESSION_BUS_ADDRESS") -- Uses os.getenv 
-  }
+    global_env = function(context)
+        return {
+            DBUS_SESSION_BUS_ADDRESS = os.getenv("DBUS_SESSION_BUS_ADDRESS") or "",
+        }
+    end
 })
 ```
 

lua/mcphub/hub.lua

@@ -77,10 +77,10 @@ end
 --- Resolve workspace-specific context
 --- @return MCPHub.JobContext|nil Workspace context or nil to fall back to global
 function MCPHub:_resolve_workspace_context()
-    local current_dir = vim.fn.getcwd()
+    local cwd = vim.fn.getcwd()
 
     -- Find workspace config
-    local workspace_info = workspace_utils.find_workspace_config(State.config.workspace.look_for, current_dir)
+    local workspace_info = workspace_utils.find_workspace_config(State.config.workspace.look_for, cwd)
 
     if not workspace_info then
         -- No workspace config found, fall back to global mode
@@ -137,10 +137,10 @@ function MCPHub:_resolve_workspace_context()
 
     return {
         port = port,
-        cwd = workspace_info.root_dir,
+        cwd = workspace_info.root_dir or cwd,
         config_files = config_files,
         is_workspace_mode = true,
-        workspace_root = workspace_info.root_dir,
+        workspace_root = workspace_info.root_dir or cwd,
         existing_hub = existing_hub, -- Include hub info from cache
     }
 end
@@ -157,7 +157,7 @@ function MCPHub:_resolve_global_context()
         cwd = cwd,
         config_files = { self.config },
         is_workspace_mode = false,
-        workspace_root = nil,
+        workspace_root = cwd,
         existing_hub = existing_hub,
     }
 end
@@ -256,7 +256,7 @@ function MCPHub:_start_server_with_context(context)
             vim.notify("Failed to serialize global_env: " .. json_env, vim.log.levels.WARN)
         end
     end
-    job_env = vim.tbl_extend("force", vim.fn.environ(), job_env or {})
+    job_env = vim.tbl_extend("force", vim.fn.environ(), { CWD = context.cwd }, job_env or {})
 
     log.debug("Starting server with context" .. vim.inspect({
         port = context.port,