Support install and uninstall backend skills flow

ai-code-backends.el

@@ -208,7 +208,7 @@ so the CLI itself handles the installation details."
      :config  "~/.claude.json"
      :agent-file "CLAUDE.md"
      :upgrade "npm install -g @anthropic-ai/claude-code@latest"
-     :install-skills ai-code-claude-code-install-skills
+     :install-skills nil
      :cli     "claude")
     (gemini
      :label "Gemini CLI"
@@ -584,16 +584,32 @@ ARG is the prefix argument to pass to the upgrade function."
   "Fallback skills installation for backend LABEL.
 Prompt user for a skills repository URL and ask the AI CLI session
 to read the repo README and install the skills."
-  (let* ((url (read-string
-               (format "Skills repo URL for %s: " label)
+  (ai-code--manage-backend-skills-fallback label 'install))
+
+(defun ai-code--manage-backend-skills-fallback (label action)
+  "Fallback backend skills management for LABEL and ACTION.
+ACTION should be the symbol `install' or `uninstall'."
+  (let* ((action-name
+          (pcase action
+            ('install "install")
+            ('uninstall "uninstall")
+            (_ (user-error
+                "Invalid backend skills action: %S; expected `install' or `uninstall'"
+                action))))
+         (url (read-string
+               (format "Skills repo URL for %s %s: " label action-name)
                nil nil "https://github.com/obra/superpowers"))
          (default-prompt
-          (format
-           "Please read the README of %s and install/setup the skills described there for %s. Follow the installation instructions in the README."
-           url label))
+          (if (eq action 'uninstall)
+              (format
+               "Please read the README of %s and uninstall/remove the skills described there for %s. Follow the repository instructions to remove any installed skill files and cleanup related configuration."
+               url label)
+            (format
+             "Please read the README of %s and install/setup the skills described there for %s. Follow the installation instructions in the README."
+             url label)))
          (prompt (if (called-interactively-p 'interactive)
                      (ai-code-read-string
-                      (format "Edit install-skills prompt for %s: " label)
+                      (format "Edit %s-skills prompt for %s: " action-name label)
                       default-prompt)
                    default-prompt)))
     (ai-code-cli-send-command prompt)))
@@ -606,15 +622,25 @@ If the backend defines an :install-skills property, use it:
   - symbol: call the function.
 Otherwise fall back to prompting the AI session to install from a
 skills repository URL."
+  ;; DONE: firstly ask user if it is install or uninstall, then ask for the repo URL if needed, and finally run install / uninstall using corresponding prompt.
   (interactive)
   (let* ((spec (ai-code--backend-spec ai-code-selected-backend)))
     (if (not spec)
         (user-error "No backend is currently selected")
       (ai-code--ensure-backend-loaded spec)
       (let* ((plist (cdr spec))
              (install-skills (plist-get plist :install-skills))
-             (label (ai-code-current-backend-label)))
+             (label (ai-code-current-backend-label))
+             (action-choice (completing-read
+                             (format "Manage skills for %s: " label)
+                             '("install" "uninstall")
+                             nil t nil nil "install"))
+             (action (if (string= action-choice "uninstall")
+                         'uninstall
+                       'install)))
         (cond
+         ((eq action 'uninstall)
+          (ai-code--manage-backend-skills-fallback label 'uninstall))
          ((stringp install-skills)
           (compile install-skills)
           (message "Running skills installation for %s" label))

ai-code.el

@@ -509,7 +509,7 @@ Shows the current backend label to the right."
   ("z" "Switch to AI CLI (C-u: hide)" ai-code-cli-switch-to-buffer-or-hide)
   ("s" ai-code-select-backend :description ai-code--select-backend-description)
   ("u" "Install / Upgrade AI CLI" ai-code-upgrade-backend)
-  ("S" "Install skills for backend" ai-code-install-backend-skills)
+  ("S" "(Un)Install skills for backend" ai-code-install-backend-skills)
   ("g" "Open backend config (eg. add mcp)" ai-code-open-backend-config)
   ("G" "Open backend repo agent file" ai-code-open-backend-agent-file)
   ("|" "Apply prompt on file" ai-code-apply-prompt-on-current-file))

test/test_ai-code-backends.el

@@ -211,17 +211,25 @@
 (ert-deftest ai-code-test-install-skills-with-string-command ()
   "Backend with :install-skills string runs it via compile."
   (let* ((compiled-cmd nil)
+         (read-string-called nil)
          (ai-code-backends '((test-backend
                                :label "Test Backend"
                                :install-skills "npm install skills"
                                :cli "test")))
          (ai-code-selected-backend 'test-backend))
-    (cl-letf (((symbol-function 'compile)
+    (cl-letf (((symbol-function 'completing-read)
+               (lambda (&rest _args) "install"))
+              ((symbol-function 'read-string)
+               (lambda (&rest _args)
+                 (setq read-string-called t)
+                 "https://github.com/obra/superpowers"))
+              ((symbol-function 'compile)
                (lambda (cmd) (setq compiled-cmd cmd)))
               ((symbol-function 'message)
                (lambda (&rest _args) nil)))
       (ai-code-install-backend-skills)
-      (should (string= compiled-cmd "npm install skills")))))
+      (should (string= compiled-cmd "npm install skills"))
+      (should-not read-string-called))))
 
 (ert-deftest ai-code-test-install-skills-with-function-symbol ()
   "Backend with :install-skills as function symbol calls that function."
@@ -231,7 +239,9 @@
                                :install-skills ai-code-test--install-skills-fn
                                :cli "test")))
          (ai-code-selected-backend 'test-backend))
-    (cl-letf (((symbol-function 'ai-code-test--install-skills-fn)
+    (cl-letf (((symbol-function 'completing-read)
+               (lambda (&rest _args) "install"))
+              ((symbol-function 'ai-code-test--install-skills-fn)
                (lambda () (setq fn-called t)))
               ((symbol-function 'message)
                (lambda (&rest _args) nil)))
@@ -241,22 +251,63 @@
 (ert-deftest ai-code-test-install-skills-fallback-when-nil ()
   "Backend without :install-skills falls back to prompting AI via send-command."
   (let* ((sent-command nil)
+         (prompted-url nil)
          (ai-code-backends '((test-backend
                                :label "Test Backend"
                                :cli "test")))
          (ai-code-selected-backend 'test-backend))
-    (cl-letf (((symbol-function 'read-string)
+    (cl-letf (((symbol-function 'completing-read)
+               (lambda (&rest _args) "install"))
+              ((symbol-function 'read-string)
                (lambda (_prompt &optional _initial _history _default &rest _rest)
+                 (setq prompted-url t)
                  "https://github.com/obra/superpowers"))
               ((symbol-function 'ai-code-cli-send-command)
                (lambda (cmd) (setq sent-command cmd)))
               ((symbol-function 'message)
                (lambda (&rest _args) nil)))
       (ai-code-install-backend-skills)
+      (should prompted-url)
       (should (stringp sent-command))
       (should (string-match-p "superpowers" sent-command))
       (should (string-match-p "README" sent-command)))))
 
+(ert-deftest ai-code-test-uninstall-skills-fallback-prompts-for-url-and-sends-command ()
+  "Uninstall should prompt for a repo URL and send an uninstall prompt."
+  (let* ((sent-command nil)
+         (prompted-url nil)
+         (ai-code-backends '((test-backend
+                               :label "Test Backend"
+                               :install-skills "npm install skills"
+                               :cli "test")))
+         (ai-code-selected-backend 'test-backend))
+    (cl-letf (((symbol-function 'completing-read)
+               (lambda (&rest _args) "uninstall"))
+              ((symbol-function 'read-string)
+               (lambda (_prompt &optional _initial _history _default &rest _rest)
+                 (setq prompted-url t)
+                 "https://github.com/obra/superpowers"))
+              ((symbol-function 'ai-code-cli-send-command)
+               (lambda (cmd) (setq sent-command cmd)))
+              ((symbol-function 'message)
+               (lambda (&rest _args) nil)))
+      (ai-code-install-backend-skills)
+      (should prompted-url)
+      (should (stringp sent-command))
+      (should (string-match-p "superpowers" sent-command))
+      (should (string-match-p "uninstall" sent-command)))))
+
+(ert-deftest ai-code-test-manage-backend-skills-fallback-errors-on-invalid-action ()
+  "Fallback helper should reject invalid backend skills actions."
+  (cl-letf (((symbol-function 'read-string)
+             (lambda (&rest _args)
+               "https://github.com/obra/superpowers"))
+            ((symbol-function 'ai-code-cli-send-command)
+             (lambda (_cmd)
+               (ert-fail "invalid action should error before sending a command"))))
+    (should-error (ai-code--manage-backend-skills-fallback "Test Backend" 'remove)
+                  :type 'user-error)))
+
 (ert-deftest ai-code-test-select-backend-shows-onboarding-hint ()
   "Explicit backend selection should show the onboarding next-step hint."
   (let* ((hint-called nil)
@@ -323,8 +374,10 @@
                                :install-skills ai-code-test-nonexistent-install-fn
                                :cli "test")))
          (ai-code-selected-backend 'test-backend))
-    (should-error (ai-code-install-backend-skills)
-                  :type 'user-error)))
+    (cl-letf (((symbol-function 'completing-read)
+               (lambda (&rest _args) "install")))
+      (should-error (ai-code-install-backend-skills)
+                    :type 'user-error))))
 
 (ert-deftest ai-code-test-claude-code-backend-has-install-skills ()
   "Claude Code backend spec should have :install-skills set to the dedicated function."