diff --git a/CHANGELOG.md b/CHANGELOG.md
index 35ef32d..6d41b0a 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,8 @@
 
 ## Unreleased
 
+- Reject surplus positional arguments instead of silently discarding them, using Commander 0.3.0 for strict command validation.
+
 - Keep numeric reminder indexes stable across reordered EventKit fetches by breaking equal due-date/title sort ties with the reminder ID.
 - Reject impossible ISO dates, malformed offsets, and trailing date text; select explicit field order so day-first inputs cannot silently become another date while retaining unambiguous legacy spellings.
 - Handle CRLF as a complete newline when removing managed URL notes and exporting CSV, preventing stale URL mirrors, split CSV records, and missed formula prefixes.
diff --git a/Package.resolved b/Package.resolved
index 5f533dc..45a958f 100644
--- a/Package.resolved
+++ b/Package.resolved
@@ -1,13 +1,13 @@
 {
-  "originHash" : "d1cb13c1640dc8cb50d58a7784a7c829ba3087e0652eaa17b387fd44e2e845db",
+  "originHash" : "f1b9f6633dcdb2bc5c64181065ee84f01f0af378e6234f652ab5db8f6c627977",
   "pins" : [
     {
       "identity" : "commander",
       "kind" : "remoteSourceControl",
       "location" : "https://github.com/steipete/Commander.git",
       "state" : {
-        "revision" : "bd219c4ee9032fee3e009856f81fcc6ec09a85f4",
-        "version" : "0.2.4"
+        "revision" : "3f5a3cb1f19ce7ca79fdc2111a09dfb3da200c1c",
+        "version" : "0.3.0"
       }
     }
   ],
diff --git a/Package.swift b/Package.swift
index b7f5e53..ba30846 100644
--- a/Package.swift
+++ b/Package.swift
@@ -9,7 +9,7 @@ let package = Package(
     .executable(name: "remindctl", targets: ["remindctl"]),
   ],
   dependencies: [
-    .package(url: "https://github.com/steipete/Commander.git", from: "0.2.0"),
+    .package(url: "https://github.com/steipete/Commander.git", from: "0.3.0"),
   ],
   targets: [
     .target(
diff --git a/README.md b/README.md
index ea0f84f..4d96048 100644
--- a/README.md
+++ b/README.md
@@ -80,7 +80,7 @@ Indexes such as `1` come from the default reminder listing. Most commands also a
 | `remindctl status` | Show Reminders permission status |
 | `remindctl authorize` | Request Reminders permission when macOS allows it |
 
-Run `remindctl <command> --help` for the full option list.
+Run `remindctl <command> --help` for the full option list. Unexpected extra arguments are rejected; quote multi-word titles and list names.
 
 ## Showing Reminders
 
diff --git a/Sources/remindctl/CommandRouter.swift b/Sources/remindctl/CommandRouter.swift
index 05edb0a..b5cfeb3 100644
--- a/Sources/remindctl/CommandRouter.swift
+++ b/Sources/remindctl/CommandRouter.swift
@@ -45,8 +45,7 @@ struct CommandRouter {
   }
 
   func run(argv: [String]) async -> Int32 {
-    var argv = normalizeArguments(argv)
-    argv = applyAliases(argv)
+    var argv = applyAliases(argv)
     let controlArguments = argv.prefix { $0 != "--" }
 
     if controlArguments.contains("--version") || controlArguments.contains("-V") {
@@ -62,7 +61,7 @@ struct CommandRouter {
     argv = rewriteImplicitShow(argv)
 
     do {
-      let invocation = try program.resolve(argv: argv)
+      let invocation = try program.resolve(arguments: [rootName] + argv.dropFirst())
       guard let commandName = invocation.path.last,
         let spec = specs.first(where: { $0.name == commandName })
       else {
@@ -91,13 +90,6 @@ struct CommandRouter {
     }
   }
 
-  private func normalizeArguments(_ argv: [String]) -> [String] {
-    guard !argv.isEmpty else { return argv }
-    var copy = argv
-    copy[0] = rootName
-    return copy
-  }
-
   private func applyAliases(_ argv: [String]) -> [String] {
     guard argv.count >= 2 else { return argv }
     var copy = argv
diff --git a/Sources/remindctl/Commands/CompleteCommand.swift b/Sources/remindctl/Commands/CompleteCommand.swift
index 5c8c7f3..25adb6a 100644
--- a/Sources/remindctl/Commands/CompleteCommand.swift
+++ b/Sources/remindctl/Commands/CompleteCommand.swift
@@ -11,7 +11,7 @@ enum CompleteCommand {
       signature: CommandSignatures.withRuntimeFlags(
         CommandSignature(
           arguments: [
-            .make(label: "ids", help: "Indexes or ID prefixes", isOptional: true)
+            .make(label: "ids", help: "Indexes or ID prefixes", isOptional: true, parsing: .remaining)
           ],
           flags: [
             .make(label: "dryRun", names: [.short("n"), .long("dry-run")], help: "Preview without changes")
diff --git a/Sources/remindctl/Commands/DeleteCommand.swift b/Sources/remindctl/Commands/DeleteCommand.swift
index 2c5ba24..1f20ec9 100644
--- a/Sources/remindctl/Commands/DeleteCommand.swift
+++ b/Sources/remindctl/Commands/DeleteCommand.swift
@@ -11,7 +11,7 @@ enum DeleteCommand {
       signature: CommandSignatures.withRuntimeFlags(
         CommandSignature(
           arguments: [
-            .make(label: "ids", help: "Indexes or ID prefixes", isOptional: true)
+            .make(label: "ids", help: "Indexes or ID prefixes", isOptional: true, parsing: .remaining)
           ],
           flags: [
             .make(label: "dryRun", names: [.short("n"), .long("dry-run")], help: "Preview without changes"),
diff --git a/Sources/remindctl/Commands/ListCommand.swift b/Sources/remindctl/Commands/ListCommand.swift
index 0decd01..1d600f6 100644
--- a/Sources/remindctl/Commands/ListCommand.swift
+++ b/Sources/remindctl/Commands/ListCommand.swift
@@ -18,7 +18,7 @@ enum ListCommand {
       signature: CommandSignatures.withRuntimeFlags(
         CommandSignature(
           arguments: [
-            .make(label: "name", help: "List name(s)", isOptional: true)
+            .make(label: "name", help: "List name(s)", isOptional: true, parsing: .remaining)
           ],
           options: [
             .make(
diff --git a/Tests/remindctlTests/CommandRouterTests.swift b/Tests/remindctlTests/CommandRouterTests.swift
index 9dfd23f..eab771b 100644
--- a/Tests/remindctlTests/CommandRouterTests.swift
+++ b/Tests/remindctlTests/CommandRouterTests.swift
@@ -3,6 +3,29 @@ import Testing
 @testable import remindctl
 
 struct CommandRouterTests {
+  @Test("Surplus command arguments are rejected")
+  func surplusArguments() async {
+    let code = await CommandRouter().run(argv: ["remindctl", "completion", "bash", "unexpected"])
+    #expect(code == 1)
+  }
+
+  @Test("Bulk commands preserve all positional values", arguments: ["list", "complete", "delete"])
+  func bulkArguments(_ command: String) throws {
+    let invocation = try CommandRouter().program.resolve(arguments: [
+      "remindctl", command, "First", "Second", "--plain",
+    ])
+    #expect(invocation.parsedValues.positional == ["First", "Second"])
+    #expect(invocation.parsedValues.flags.contains("plainOutput"))
+  }
+
+  @Test(
+    "Single-target commands reject extra positionals", arguments: ["add", "edit", "search", "info", "link", "open"])
+  func singleTargetArguments(_ command: String) {
+    #expect(throws: (any Error).self) {
+      try CommandRouter().program.resolve(arguments: ["remindctl", command, "First", "Second"])
+    }
+  }
+
   @Test("A renamed executable resolves the canonical command")
   func renamedExecutable() async {
     let code = await CommandRouter().run(argv: ["/tmp/custom-reminders", "completion", "bash"])
diff --git a/Tests/remindctlTests/ListActionTests.swift b/Tests/remindctlTests/ListActionTests.swift
index 4745893..2ddf1a4 100644
--- a/Tests/remindctlTests/ListActionTests.swift
+++ b/Tests/remindctlTests/ListActionTests.swift
@@ -5,7 +5,7 @@ import Testing
 
 struct ListActionTests {
   private func action(_ arguments: [String]) throws -> ListCommand.Action {
-    let values = try CommandRouter().program.resolve(argv: ["remindctl", "list"] + arguments).parsedValues
+    let values = try CommandRouter().program.resolve(arguments: ["remindctl", "list"] + arguments).parsedValues
     return try ListCommand.action(
       names: values.positional,
       listID: values.option("listID"),