diff --git a/app/assets/stylesheets/terminals.css b/app/assets/stylesheets/terminals.css
index c854106f3..6c8f4bfb6 100644
--- a/app/assets/stylesheets/terminals.css
+++ b/app/assets/stylesheets/terminals.css
@@ -69,10 +69,57 @@
     .terminal--open & {
       display: flex;
     }
+
+    .terminal--showing-help & {
+      display: none;
+    }
+  }
+
+  .terminal__help {
+    display: none;
+
+    .terminal--showing-help & {
+      border-block-end: 1px dashed;
+      display: block;
+      margin-block-end: 0.5lh;
+      padding-block-end: 0.5lh;
+    }
+
+    h2 {
+      border-block-end: 1px dashed;
+      font-size: var(--text-normal);
+      font-weight: normal;
+      margin-block: 0 0.5lh;
+      padding-block-end: 0.5lh;
+    }
+
+    h3 {
+      font-size: var(--text-small);
+      margin-block: 0;
+      text-transform: uppercase;
+    }
+
+    dl {
+      display: grid;
+      grid-template-columns: min-content 1fr;
+      gap: 0.5em 1em;
+      font-size: var(--text-small);
+      margin: 0;
+    }
+
+    dt {
+      grid-column: 1;
+      margin-inline-start: var(--inline-space-double);
+      white-space: nowrap;
+    }
+
+    dd {
+      grid-column: 2;
+    }
   }
 
   .terminal__item {
-    &:where(:not(:active)):focus-visible {
+    &:where(:not(:active)):focus-visible, &:where(:not(:active))[aria-current] {
       --btn-color: var(--color-terminal-bg);
 
       background: var(--color-terminal-text);
diff --git a/app/javascript/controllers/navigable_list_controller.js b/app/javascript/controllers/navigable_list_controller.js
index 4951517d9..ca798e62b 100644
--- a/app/javascript/controllers/navigable_list_controller.js
+++ b/app/javascript/controllers/navigable_list_controller.js
@@ -13,6 +13,10 @@ export default class extends Controller {
     }
   }
 
+  select({ target }) {
+    this.#setCurrentFrom(target)
+  }
+
   selectCurrentOrLast(event) {
     if (this.currentItem) {
       this.#setCurrentFrom(this.currentItem)
diff --git a/app/javascript/controllers/terminal_controller.js b/app/javascript/controllers/terminal_controller.js
index 65aaca9a3..0e43293aa 100644
--- a/app/javascript/controllers/terminal_controller.js
+++ b/app/javascript/controllers/terminal_controller.js
@@ -3,7 +3,11 @@ import { HttpStatus } from "helpers/http_helpers"
 
 export default class extends Controller {
   static targets = [ "input", "form", "confirmation" ]
-  static classes = [ "error", "confirmation" ]
+  static classes = [ "error", "confirmation", "help" ]
+
+  disconnect() {
+    if (this.waitingForConfirmation) { this.#reset() }
+  }
 
   // Actions
 
@@ -12,6 +16,28 @@ export default class extends Controller {
   }
 
   executeCommand(event) {
+    if (this.#showHelpCommandEntered) {
+      this.#showHelpMenu()
+      event.preventDefault()
+      event.stopPropagation()
+    } else {
+      this.hideHelpMenu()
+    }
+  }
+
+  hideHelpMenu() {
+    if (this.#showHelpCommandEntered) { this.#reset() }
+    this.element.classList.remove(this.helpClass)
+  }
+
+  handleKeyPress(event) {
+    if (this.waitingForConfirmation) {
+      this.#handleConfirmationKey(event.key.toLowerCase())
+      event.preventDefault()
+    }
+  }
+
+  handleCommandResponse(event) {
     if (event.detail.success) {
       this.#reset()
     } else {
@@ -32,6 +58,18 @@ export default class extends Controller {
     this.element.classList.remove(this.errorClass)
   }
 
+  get #showHelpCommandEntered() {
+    return [ "/help", "/?" ].includes(this.inputTarget.value)
+  }
+
+  #showHelpMenu() {
+    this.element.classList.add(this.helpClass)
+  }
+
+  get #isHelpMenuOpened() {
+    return this.element.classList.contains(this.helpClass)
+  }
+
   async #handleErrorResponse(response) {
     const status = response.status
     const message = await response.text()
@@ -47,6 +85,8 @@ export default class extends Controller {
     this.formTarget.reset()
     this.inputTarget.value = inputValue
     this.confirmationTarget.value = ""
+    this.waitingForConfirmation = false
+    this.originalInputValue = null
 
     this.element.classList.remove(this.errorClass)
     this.element.classList.remove(this.confirmationClass)
@@ -57,35 +97,23 @@ export default class extends Controller {
   }
 
   async #requestConfirmation(message) {
-    const originalInputValue = this.inputTarget.value
+    this.originalInputValue = this.inputTarget.value
     this.element.classList.add(this.confirmationClass)
-    this.inputTarget.value = `${message}? [y/n] `
+    this.inputTarget.value = `${message}? [Y/n] `
 
-    try {
-      await this.#waitForConfirmation()
-      this.#submitWithConfirmation(originalInputValue)
-    } catch {
-      this.#reset(originalInputValue)
+    this.waitingForConfirmation = true
+  }
+
+  #handleConfirmationKey(key) {
+    if (key === "enter" || key === "y") {
+      this.#submitWithConfirmation()
+    } else if (key === "escape" || key === "n") {
+      this.#reset(this.originalInputValue)
     }
   }
 
-  #waitForConfirmation() {
-    return new Promise((resolve, reject) => {
-      this.inputTarget.addEventListener("keydown", (event) => {
-        event.preventDefault()
-        const key = event.key.toLowerCase()
-
-        if (key === "enter" || key === "y") {
-          resolve()
-        } else {
-          reject()
-        }
-      }, { once: true })
-    })
-  }
-
-  #submitWithConfirmation(inputValue) {
-    this.inputTarget.value = inputValue
+  #submitWithConfirmation() {
+    this.inputTarget.value = this.originalInputValue
     this.confirmationTarget.value = "confirmed"
     this.formTarget.requestSubmit()
   }
diff --git a/app/models/command/clear_filters.rb b/app/models/command/clear_filters.rb
new file mode 100644
index 000000000..90685d00e
--- /dev/null
+++ b/app/models/command/clear_filters.rb
@@ -0,0 +1,20 @@
+class Command::ClearFilters < Command
+  store_accessor :data, :params
+
+  def title
+    "Clear filters"
+  end
+
+  def execute
+    redirect_to cards_path(**params.to_h.with_indifferent_access.without(*filters_to_clear))
+  end
+
+  private
+    FILTERS_TO_KEEP = [ :collection_ids, :indexed_by ]
+
+    def filters_to_clear
+      Filter::Params::PERMITTED_PARAMS
+        .flat_map { |param| param.is_a?(Hash) ? param.keys : param }
+        .without(*FILTERS_TO_KEEP)
+    end
+end
diff --git a/app/models/command/filter_by_tag.rb b/app/models/command/filter_by_tag.rb
new file mode 100644
index 000000000..f62aca01a
--- /dev/null
+++ b/app/models/command/filter_by_tag.rb
@@ -0,0 +1,13 @@
+class Command::FilterByTag < Command
+  include Command::Tags
+
+  store_accessor :data, :params
+
+  def title
+    "Filter by tag ##{tag_title}"
+  end
+
+  def execute
+    redirect_to cards_path(**params.merge(tag_ids: [ tag.id ]))
+  end
+end
diff --git a/app/models/command/parser.rb b/app/models/command/parser.rb
index 830b6c93d..c2c98fcb7 100644
--- a/app/models/command/parser.rb
+++ b/app/models/command/parser.rb
@@ -19,12 +19,18 @@ class Command::Parser
       command_name, *command_arguments = string.strip.split(" ")
 
       case command_name
-      when "/assign", "/assignto"
-        Command::Assign.new(assignee_ids: assignees_from(command_arguments).collect(&:id), card_ids: cards.ids)
-      when "/close"
-        Command::Close.new(card_ids: cards.ids, reason: command_arguments.join(" "))
+      when /^#/
+        Command::FilterByTag.new(tag_title: tag_title_from(string), params: filter.as_params)
       when /^@/
         Command::GoToUser.new(user_id: assignee_from(command_name)&.id)
+      when "/assign", "/assignto"
+        Command::Assign.new(assignee_ids: assignees_from(command_arguments).collect(&:id), card_ids: cards.ids)
+      when "/clear"
+        Command::ClearFilters.new(params: filter.as_params)
+      when "/close"
+        Command::Close.new(card_ids: cards.ids, reason: command_arguments.join(" "))
+      when "/tag"
+        Command::Tag.new(tag_title: tag_title_from(command_arguments.join(" ")), card_ids: cards.ids)
       else
         parse_free_string(string)
       end
@@ -44,6 +50,10 @@ class Command::Parser
       User.all.find { |user| user.mentionable_handles.include?(string_without_at) }
     end
 
+    def tag_title_from(string)
+      string.gsub(/^#/, "")
+    end
+
     def parse_free_string(string)
       if cards = multiple_cards_from(string)
         Command::FilterCards.new(card_ids: cards.ids, params: filter.as_params)
diff --git a/app/models/command/parser/context.rb b/app/models/command/parser/context.rb
index 09591ce72..fae468efb 100644
--- a/app/models/command/parser/context.rb
+++ b/app/models/command/parser/context.rb
@@ -10,7 +10,7 @@ class Command::Parser::Context
     if controller == "cards" && action == "show"
       user.accessible_cards.where id: params[:id]
     elsif controller == "cards" && action == "index"
-      filter.cards
+      filter.cards.published
     else
       Card.none
     end
diff --git a/app/models/command/tag.rb b/app/models/command/tag.rb
new file mode 100644
index 000000000..c6596de56
--- /dev/null
+++ b/app/models/command/tag.rb
@@ -0,0 +1,37 @@
+class Command::Tag < Command
+  include Command::Cards, Command::Tags
+
+  store_accessor :data, :tagged_card_ids
+
+  def title
+    "Tag #{cards_description} with ##{tag_title}"
+  end
+
+  def execute
+    tagged_card_ids = []
+
+    transaction do
+      cards.find_each do |card|
+        unless card.tagged_with?(tag)
+          tagged_card_ids << card.id
+          card.toggle_tag_with(tag_title)
+        end
+      end
+
+      update! tagged_card_ids: tagged_card_ids
+    end
+  end
+
+  def undo
+    transaction do
+      tagged_cards.find_each do |card|
+        card.toggle_tag_with(tag_title) if card.tagged_with?(tag)
+      end
+    end
+  end
+
+  private
+    def tagged_cards
+      user.accessible_cards.where(id: tagged_card_ids)
+    end
+end
diff --git a/app/models/command/tags.rb b/app/models/command/tags.rb
new file mode 100644
index 000000000..448c7375c
--- /dev/null
+++ b/app/models/command/tags.rb
@@ -0,0 +1,14 @@
+module Command::Tags
+  extend ActiveSupport::Concern
+
+  included do
+    store_accessor :data, :tag_title
+
+    validates_presence_of :tag_title
+  end
+
+  private
+    def tag
+      Tag.find_or_create_by!(title: tag_title)
+    end
+end
diff --git a/app/models/filter.rb b/app/models/filter.rb
index 772e80c8b..a92b3a402 100644
--- a/app/models/filter.rb
+++ b/app/models/filter.rb
@@ -19,8 +19,8 @@ class Filter < ApplicationRecord
   def cards
     @cards ||= begin
       result = creator.accessible_cards.indexed_by(indexed_by)
-      result = result.where(id: card_ids) if card_ids.present? && !indexed_by.closed?
-      result = result.open unless indexed_by.closed?
+      result = result.where(id: card_ids) if card_ids.present?
+      result = result.open unless indexed_by.closed? || card_ids.present?
       result = result.by_engagement_status(engagement_status) if engagement_status.present?
       result = result.unassigned if assignment_status.unassigned?
       result = result.assigned_to(assignees.ids) if assignees.present?
diff --git a/app/views/commands/_form.html.erb b/app/views/commands/_form.html.erb
index ece1cc8ee..40d04fa56 100644
--- a/app/views/commands/_form.html.erb
+++ b/app/views/commands/_form.html.erb
@@ -4,7 +4,8 @@
       data: {
         controller: "form",
         terminal_target: "form",
-        action: "turbo:submit-end->terminal#focus keydown.meta+k@document->terminal#focus turbo:submit-end->terminal#executeCommand"
+        turbo_permanent: true,
+        action: "turbo:submit-end->terminal#focus keydown.meta+k@document->terminal#focus keydown.enter->terminal#executeCommand keydown.esc->terminal#hideHelpMenu turbo:submit-end->terminal#handleCommandResponse"
       } do %>
   <label class="terminal__label txt-nowrap" for="fizzy_do">Fizzy do &gt;</label>
 
@@ -15,8 +16,7 @@
         class: "terminal__input input fill-transparent unpad",
         data: {
           terminal_target: "input",
-          action: "keydown.up->toggle-class#add:prevent keydown.up->navigable-list#selectCurrentOrLast terminal#hideError",
-          turbo_permanent: true
+          action: "keydown.up->toggle-class#add:prevent keydown.up->navigable-list#selectCurrentOrLast terminal#hideError"
         },
         placeholder: "Press ⌘+K to search or type commands…",
         spellcheck: "false" %>
diff --git a/app/views/commands/_help.html.erb b/app/views/commands/_help.html.erb
new file mode 100644
index 000000000..8c18abcf3
--- /dev/null
+++ b/app/views/commands/_help.html.erb
@@ -0,0 +1,28 @@
+<section class="terminal__help" aria-labelledby="help-menu-title">
+  <h2 id="help-menu-title">Commands you can use in Fizzy:</h2>
+  <dl>
+    <h3>Navigation</h3>
+    <dt><code>@username</code></dt>
+    <dd>Navigate to a someone's profile</dd>
+    <dt><code>[card id]</code></dt>
+    <dd>Navigate to a specific card by its id</dd>
+
+    <h3>Filtering</h3>
+    <dt><code>#tag_name</code></dt>
+    <dd>Filter cards by tag</dd>
+    <dt><code>[card id 1] [card id 2]...</code></dt>
+    <dd>Filter multiple cards by their IDs</dd>
+    <dt><code>search_term</code></dt>
+    <dd>Search for cards containing the term</dd>
+    <dt><code>/clear</code></dt>
+    <dd>Clear all the filters</dd>
+
+    <h3>Cards</h3>
+    <dt><code>/assign [username 1] [username 2]...</code></dt>
+    <dd>Assign selected cards to specified people(s)</dd>
+    <dt><code>/close [reason]</code></dt>
+    <dd>Close selected card(s) with an optional reason</dd>
+    <dt><code>/tag [tag name]</code></dt>
+    <dd>Add a tag to selected cards</dd>
+  </dl>
+</section>
diff --git a/app/views/commands/_terminal.html.erb b/app/views/commands/_terminal.html.erb
index 31395cb47..6efee7eff 100644
--- a/app/views/commands/_terminal.html.erb
+++ b/app/views/commands/_terminal.html.erb
@@ -2,8 +2,9 @@
       controller: "toggle-class terminal navigable-list",
       terminal_error_class: "terminal--error",
       terminal_confirmation_class: "terminal--confirmation",
+      terminal_help_class: "terminal--showing-help",
       toggle_class_toggle_class: "terminal--open",
-      action: "keydown->navigable-list#navigate keydown.esc->toggle-class#remove:stop keydown.esc->terminal#focus keydown.esc->navigable-list#selectLast" } do %>
+      action: "keydown->terminal#handleKeyPress keydown->navigable-list#navigate focusin->navigable-list#select keydown.esc->toggle-class#remove:stop keydown.esc->terminal#focus keydown.esc->navigable-list#selectLast keydown.esc@document->terminal#hideHelpMenu" } do %>
   <%= turbo_frame_tag :recent_commands, src: commands_path, refresh: "morph" %>
 
   <%= render "commands/form" %>
diff --git a/app/views/commands/index.html.erb b/app/views/commands/index.html.erb
index 49126efbe..b3369ab85 100644
--- a/app/views/commands/index.html.erb
+++ b/app/views/commands/index.html.erb
@@ -2,4 +2,6 @@
   <ul class="terminal__menu flex-column txt-align-start margin-none margin-block-end unpad" aria-label="Recent commands">
     <%= render partial: "commands/command", collection: @commands %>
   </ul>
+
+  <%= render "commands/help" %>
 <% end %>
diff --git a/app/views/filters/_cards.html.erb b/app/views/filters/_cards.html.erb
new file mode 100644
index 000000000..fe9b61cd0
--- /dev/null
+++ b/app/views/filters/_cards.html.erb
@@ -0,0 +1,3 @@
+<% if filter.card_ids.present? %>
+  <%= filter_chip_tag "Cards #{filter.card_ids.join(", ")}", filter.as_params.without(:card_ids) %>
+<% end %>
diff --git a/app/views/filters/_settings.html.erb b/app/views/filters/_settings.html.erb
index 850cd786e..9852304d8 100644
--- a/app/views/filters/_settings.html.erb
+++ b/app/views/filters/_settings.html.erb
@@ -4,6 +4,7 @@
     <%= render "filters/assignees", filter: filter %>
     <%= render "filters/creators", filter: filter %>
     <%= render "filters/stages", filter: filter %>
+    <%= render "filters/cards", filter: filter %>
 
     <% filter.terms.each do |term| %>
       <%= filter_chip_tag %Q("#{term}"), filter.as_params_without(:terms, term) %>
diff --git a/test/models/command/assign_test.rb b/test/models/command/assign_test.rb
index 705dad10e..89cda1d81 100644
--- a/test/models/command/assign_test.rb
+++ b/test/models/command/assign_test.rb
@@ -8,7 +8,7 @@ class Command::AssignTest < ActionDispatch::IntegrationTest
     @card = cards(:text)
   end
 
-  test "assigns card on perma" do
+  test "assign card on perma" do
     assert_difference -> { @card.assignees.count }, +2 do
       execute_command "/assign @kevin @david", context_url: collection_card_url(@card.collection, @card)
     end
@@ -17,7 +17,7 @@ class Command::AssignTest < ActionDispatch::IntegrationTest
     assert_includes @card.assignees, users(:kevin)
   end
 
-  test "assigns cards on cards' index page" do
+  test "assign cards on cards' index page" do
     execute_command "/assign @kevin @david", context_url: collection_cards_url(@card.collection)
 
     cards(:logo, :text, :layout).each do |card|
diff --git a/test/models/command/clear_filters_test.rb b/test/models/command/clear_filters_test.rb
new file mode 100644
index 000000000..aa5fe1a5f
--- /dev/null
+++ b/test/models/command/clear_filters_test.rb
@@ -0,0 +1,15 @@
+require "test_helper"
+
+class Command::FilterTest < ActionDispatch::IntegrationTest
+  include CommandTestHelper
+
+  setup do
+    Current.session = sessions(:david)
+  end
+
+  test "clear the filters keeping the selected collections" do
+    result = execute_command "/clear", context_url: "?card_ids%5B%5D=1&card_ids%5B%5D=2&collection_ids%5B%5D=#{collections(:writebook).id}&indexed_by=newest&terms%5B%5D=jorge"
+
+    assert_equal cards_path(indexed_by: "newest", collection_ids: [ collections(:writebook).id ]), result.url
+  end
+end
diff --git a/test/models/command/close_test.rb b/test/models/command/close_test.rb
index abdb821b3..138e37aa4 100644
--- a/test/models/command/close_test.rb
+++ b/test/models/command/close_test.rb
@@ -8,7 +8,7 @@ class Command::CloseTest < ActionDispatch::IntegrationTest
     @card = cards(:text)
   end
 
-  test "closes card on perma" do
+  test "close card on perma" do
     assert_changes -> { @card.reload.closed? }, from: false, to: true do
       execute_command "/close", context_url: collection_card_url(@card.collection, @card)
     end
@@ -17,7 +17,7 @@ class Command::CloseTest < ActionDispatch::IntegrationTest
     assert_equal users(:david), @card.closed_by
   end
 
-  test "closes card on perma with reason" do
+  test "close card on perma with reason" do
     assert_changes -> { @card.reload.closed? }, from: false, to: true do
       execute_command "/close Not now", context_url: collection_card_url(@card.collection, @card)
     end
@@ -26,26 +26,26 @@ class Command::CloseTest < ActionDispatch::IntegrationTest
     assert_equal "Not now", @card.closure.reason
   end
 
-  test "closes cards on cards' index page" do
-    cards_to_check = cards(:logo, :text, :layout)
-    cards_to_check.each(&:reopen)
+  test "close cards on cards' index page" do
+    cards = cards(:logo, :text, :layout)
+    cards.each(&:reopen)
 
     execute_command "/close", context_url: collection_cards_url(@card.collection)
 
-    cards_to_check.each { it.reload.closed? }
+    cards.each { it.reload.closed? }
   end
 
-  test "undo closing" do
-    cards_to_check = cards(:logo, :text, :layout)
-    cards_to_check.each(&:reopen)
+  test "undo close" do
+    cards = cards(:logo, :text, :layout)
+    cards.each(&:reopen)
 
     command = parse_command "/close", context_url: collection_cards_url(@card.collection)
     command.execute
 
-    cards_to_check.each { it.reload.closed? }
+    cards.each { it.reload.closed? }
 
     command.undo
 
-    cards_to_check.each { it.reload.open? }
+    cards.each { it.reload.open? }
   end
 end
diff --git a/test/models/command/filter_by_tag_test.rb b/test/models/command/filter_by_tag_test.rb
new file mode 100644
index 000000000..53be19ca9
--- /dev/null
+++ b/test/models/command/filter_by_tag_test.rb
@@ -0,0 +1,15 @@
+require "test_helper"
+
+class Command::FilterByCardTest < ActionDispatch::IntegrationTest
+  include CommandTestHelper
+
+  setup do
+    @tag = tags(:web)
+  end
+
+  test "redirect to the cards index filtering by cards" do
+    result = execute_command "##{@tag.title}"
+
+    assert_equal cards_path(indexed_by: "newest", tag_ids: [ @tag.id ]), result.url
+  end
+end
diff --git a/test/models/command/filter_cards_test.rb b/test/models/command/filter_cards_test.rb
index 0280157fe..f54cd1729 100644
--- a/test/models/command/filter_cards_test.rb
+++ b/test/models/command/filter_cards_test.rb
@@ -7,13 +7,13 @@ class Command::FilterCardsTest < ActionDispatch::IntegrationTest
     @card_ids = cards(:logo, :layout).collect(&:id)
   end
 
-  test "redirects to the cards index filtering by cards" do
+  test "redirect to the cards index filtering by cards" do
     result = execute_command "#{@card_ids.join(" ")}"
 
     assert_equal cards_path(indexed_by: "newest", card_ids: @card_ids), result.url
   end
 
-  test "respects existing filters" do
+  test "respect existing filters" do
     result = execute_command "#{@card_ids.join(",")}", context_url: "http://37signals.fizzy.localhost:3006/cards?collection_ids%5B%5D=#{collections(:writebook).id}"
 
     assert_equal cards_path(indexed_by: "newest", collection_ids: [ collections(:writebook).id ], card_ids: @card_ids), result.url
diff --git a/test/models/command/go_to_card_test.rb b/test/models/command/go_to_card_test.rb
index 6078bb298..fe6e13591 100644
--- a/test/models/command/go_to_card_test.rb
+++ b/test/models/command/go_to_card_test.rb
@@ -7,13 +7,13 @@ class Command::GoToCardTest < ActionDispatch::IntegrationTest
     @card = cards(:logo)
   end
 
-  test "redirects to the card perma" do
+  test "redirect to the card perma" do
     result = execute_command "#{@card.id}"
 
     assert_equal @card, result.url
   end
 
-  test "results in a regular search if the card does not exist" do
+  test "result in a regular search if the card does not exist" do
     command = parse_command "123"
     assert command.valid?
 
diff --git a/test/models/command/go_to_user_test.rb b/test/models/command/go_to_user_test.rb
index bb11648f5..6c6247186 100644
--- a/test/models/command/go_to_user_test.rb
+++ b/test/models/command/go_to_user_test.rb
@@ -3,13 +3,13 @@ require "test_helper"
 class Command::GoToUserTest < ActionDispatch::IntegrationTest
   include CommandTestHelper
 
-  test "redirects to the user perma" do
+  test "redirect to the user perma" do
     result = execute_command "@kevin"
 
     assert_equal users(:kevin), result.url
   end
 
-  test "results in an invalid command if the user does not exist" do
+  test "result in an invalid command if the user does not exist" do
     command = parse_command "@not_a_user"
     assert !command.valid?
   end
diff --git a/test/models/command/search_test.rb b/test/models/command/search_test.rb
index 57e8d900d..7a394f8e3 100644
--- a/test/models/command/search_test.rb
+++ b/test/models/command/search_test.rb
@@ -3,13 +3,13 @@ require "test_helper"
 class Command::SearchTest < ActionDispatch::IntegrationTest
   include CommandTestHelper
 
-  test "redirects to the cards index filtering by search terms" do
+  test "redirect to the cards index filtering by search terms" do
     result = execute_command "some text"
 
     assert_equal cards_path(indexed_by: "newest", terms: [ "some text" ]), result.url
   end
 
-  test "respects existing filters" do
+  test "respect existing filters" do
     result = execute_command "some text", context_url: "http://37signals.fizzy.localhost:3006/cards?collection_ids%5B%5D=#{collections(:writebook).id}"
 
     assert_equal cards_path(indexed_by: "newest", collection_ids: [ collections(:writebook).id ], terms: [ "some text" ]), result.url
diff --git a/test/models/command/tag_test.rb b/test/models/command/tag_test.rb
new file mode 100644
index 000000000..7ac9a7b66
--- /dev/null
+++ b/test/models/command/tag_test.rb
@@ -0,0 +1,47 @@
+require "test_helper"
+
+class Command::TagTest < ActionDispatch::IntegrationTest
+  include CommandTestHelper
+
+  setup do
+    Current.session = sessions(:david)
+    @card = cards(:text)
+    @tag = tags(:web)
+  end
+
+  test "tag card on perma with existing tag" do
+    assert_changes -> { @card.tagged_with?(@tag) }, from: false, to: true do
+      execute_command "/tag #{@tag.title}", context_url: collection_card_url(@card.collection, @card)
+    end
+  end
+
+  test "tag card on perma with new tag" do
+    assert_difference -> { @card.tags.count }, +1 do
+      execute_command "/tag some-new-tag", context_url: collection_card_url(@card.collection, @card)
+    end
+
+    assert_equal "some-new-tag", @card.tags.last.title
+  end
+
+  test "tag several cards on cards' index page" do
+    cards = cards(:logo, :text, :layout)
+    cards.each { it.taggings.destroy_all }
+
+    execute_command "/tag #{@tag.title}", context_url: collection_cards_url(@card.collection)
+
+    cards.each { assert it.reload.tagged_with?(@tag) }
+  end
+
+  test "undo tagged cards" do
+    cards = cards(:logo, :text, :layout)
+    cards.each { it.taggings.destroy_all }
+
+    command = parse_command "/tag #{@tag.title}", context_url: collection_cards_url(@card.collection)
+    command.execute
+
+    cards.each { assert it.reload.tagged_with?(@tag) }
+
+    command.undo
+    cards.each { assert_not it.reload.tagged_with?(@tag) }
+  end
+end