support reading headers from a file instead of cli args

README.md

@@ -34,7 +34,9 @@ All the most popular MCP clients (Claude Desktop, Cursor & Windsurf) use the fol
 
 ### Custom Headers
 
-To bypass authentication, or to emit custom headers on all requests to your remote server, pass `--header` CLI arguments:
+To bypass authentication, or to emit custom headers on all requests to your remote server, there are two options:
+
+#### Option 1: Using `--header` CLI arguments
 
 ```json
 {
@@ -72,6 +74,33 @@ To bypass authentication, or to emit custom headers on all requests to your remo
 },
 ```
 
+#### Option 2: Using `--headerFile` to read headers from a file
+
+You can also provide headers from a file using the `--headerFile` argument. The file should contain one header per line in the format `Name:Value`. Lines starting with `#` are treated as comments and ignored.
+
+```json
+{
+  "mcpServers": {
+    "remote-example": {
+      "command": "npx",
+      "args": [
+        "mcp-remote",
+        "https://remote.mcp.server/sse",
+        "--headerFile",
+        "/path/to/headers.txt"
+      ]
+    },
+  }
+}
+```
+
+Example headers file:
+```
+# Headers for MCP Remote
+Authorization:Bearer my-token
+X-Custom-Header:custom-value
+```
+
 ### Flags
 
 * If `npx` is producing errors, consider adding `-y` as the first argument to auto-accept the installation of the `mcp-remote` package.

src/lib/utils.ts

@@ -428,6 +428,29 @@ export async function parseCommandLineArgs(args: string[], usage: string) {
       args.splice(i, 2)
       // Do not increment i, as the array has shifted
       continue
+    } else if (args[i] === '--headerFile' && i < args.length - 1) {
+      const filePath = args[i + 1]
+      try {
+        const fileContent = fs.readFileSync(filePath, 'utf8')
+        const lines = fileContent.split('\n')
+        for (const line of lines) {
+          const trimmedLine = line.trim()
+          if (trimmedLine && !trimmedLine.startsWith('#')) {
+            const match = trimmedLine.match(/^([A-Za-z0-9_-]+):(.*)$/)
+            if (match) {
+              headers[match[1]] = match[2]
+            } else {
+              log(`Warning: ignoring invalid header in file: ${trimmedLine}`)
+            }
+          }
+        }
+        log(`Loaded headers from file: ${filePath}`)
+      } catch (error) {
+        log(`Error reading header file ${filePath}: ${error.message}`)
+      }
+      args.splice(i, 2)
+      // Do not increment i, as the array has shifted
+      continue
     }
     i++
   }