feat(cli): refresh gander-skill during gander --upgrade

README.md

@@ -79,7 +79,7 @@ mv gander ~/go/bin/gander  # or any directory in your PATH
 gander --upgrade
 ```
 
-Downloads the latest release binary that matches your OS/arch, verifies its SHA256 checksum, and atomically replaces the running binary. Sets `GITHUB_TOKEN` in the environment to raise the API rate limit on shared networks.
+Downloads the latest release binary that matches your OS/arch, verifies its SHA256 checksum, and atomically replaces the running binary. If `~/.gander/skill` is already installed, the same command also pulls the latest [`gandermd/gander-skill`](https://github.com/gandermd/gander-skill) and re-links agent dests. Sets `GITHUB_TOKEN` in the environment to raise the API rate limit on shared networks.
 
 If you built from source the old-fashioned way, re-run `install.sh` (or `git pull && ./install.sh --source`).
 
@@ -257,6 +257,7 @@ The legacy `~/.mdp` fallback only applies when `GANDER_CONFIG` is unset; named p
     Download and install the latest release, then exit. The runner is shut
     down over UDS first, the binary is replaced, then the supervisor (or a
     fresh spawn) brings the upgraded daemon back up with the same watches.
+    If the agent skill is already installed, also refreshes ~/.gander/skill.
 ```
 
 Subcommands:

man/man1/gander.1

@@ -117,6 +117,8 @@ or debugging the watcher itself.
 .TP
 .BR \-upgrade ", " \-\-upgrade
 Download and install the latest release, then exit.
+If the agent skill is already installed, also refresh
+.IR ~/.gander/skill .
 .TP
 .BR \-\-help ", " \-h
 Print help and exit.
@@ -322,6 +324,15 @@ instead.
 .BR \-\-upgrade
 Download the latest release binary for the current platform, verify its
 checksum, atomically replace the running binary, and exit.
+If
+.I ~/.gander/skill
+(or a dest symlink pointing at it) is already present, also pull the
+latest
+.B gandermd/gander-skill
+and re-link the agent skill directories, matching
+.BR "gander skill" .
+A skill refresh failure does not undo a successful binary replace; the
+command still exits non-zero.
 .SH FILES
 .TP
 .I ~/.gander

skill.go

@@ -33,6 +33,33 @@ func runSkill(args []string) error {
 	return fmt.Errorf("usage: gander skill [install]")
 }
 
+func skillAlreadyInstalled() bool {
+	home, err := os.UserHomeDir()
+	if err != nil {
+		return false
+	}
+	skillDir := filepath.Join(home, ".gander", "skill")
+	if _, err := os.Stat(filepath.Join(skillDir, "SKILL.md")); err == nil {
+		return true
+	}
+	for _, d := range skillDests {
+		if isOurSkillLink(filepath.Join(home, d.rel), skillDir) {
+			return true
+		}
+	}
+	return false
+}
+
+func refreshSkillIfInstalled() error {
+	if !skillAlreadyInstalled() {
+		return nil
+	}
+	if err := runSkillInstall(); err != nil {
+		return fmt.Errorf("skill: %w", err)
+	}
+	return nil
+}
+
 func runSkillInstall() error {
 	home, err := os.UserHomeDir()
 	if err != nil {

skill_test.go

@@ -162,6 +162,44 @@ func TestSkillInstallPrefersAgentsLayout(t *testing.T) {
 	}
 }
 
+func TestSkillAlreadyInstalled(t *testing.T) {
+	home := t.TempDir()
+	t.Setenv("HOME", home)
+	if skillAlreadyInstalled() {
+		t.Fatal("want false when nothing installed")
+	}
+
+	skillDir := filepath.Join(home, ".gander", "skill")
+	if err := os.MkdirAll(skillDir, 0700); err != nil {
+		t.Fatal(err)
+	}
+	if skillAlreadyInstalled() {
+		t.Fatal("empty skill dir without SKILL.md is not installed")
+	}
+	if err := os.WriteFile(filepath.Join(skillDir, "SKILL.md"), []byte("# Gander\n"), 0644); err != nil {
+		t.Fatal(err)
+	}
+	if !skillAlreadyInstalled() {
+		t.Fatal("want true when ~/.gander/skill/SKILL.md exists")
+	}
+}
+
+func TestSkillAlreadyInstalledDestSymlink(t *testing.T) {
+	home := t.TempDir()
+	t.Setenv("HOME", home)
+	skillDir := filepath.Join(home, ".gander", "skill")
+	dest := filepath.Join(home, ".claude", "skills", "gander")
+	if err := os.MkdirAll(filepath.Dir(dest), 0755); err != nil {
+		t.Fatal(err)
+	}
+	if err := os.Symlink(skillDir, dest); err != nil {
+		t.Fatal(err)
+	}
+	if !skillAlreadyInstalled() {
+		t.Fatal("want true when a dest is our skill symlink")
+	}
+}
+
 func TestSkillRejectsBadUsage(t *testing.T) {
 	err := runSkill([]string{"foo"})
 	if err == nil {

upgrade.go

@@ -61,42 +61,42 @@ func runUpgrade() error {
 
 	if Version != "dev" && rel.TagName == Version {
 		fmt.Println("Already on the latest version.")
-		return nil
-	}
+	} else {
+		assetName := assetNameForRuntime()
+		asset, ok := findAsset(rel.Assets, assetName)
+		if !ok {
+			return fmt.Errorf("no release asset named %s in %s; available: %s",
+				assetName, rel.HTMLURL, listAssetNames(rel.Assets))
+		}
 
-	assetName := assetNameForRuntime()
-	asset, ok := findAsset(rel.Assets, assetName)
-	if !ok {
-		return fmt.Errorf("no release asset named %s in %s; available: %s",
-			assetName, rel.HTMLURL, listAssetNames(rel.Assets))
-	}
+		fmt.Printf("Found %s, downloading %s...\n", rel.TagName, assetName)
 
-	fmt.Printf("Found %s, downloading %s...\n", rel.TagName, assetName)
+		binPath, err := downloadToTemp(asset.BrowserDownloadURL)
+		if err != nil {
+			return fmt.Errorf("download: %w", err)
+		}
+		defer os.Remove(binPath)
 
-	binPath, err := downloadToTemp(asset.BrowserDownloadURL)
-	if err != nil {
-		return fmt.Errorf("download: %w", err)
-	}
-	defer os.Remove(binPath)
+		sum, err := downloadSha256(asset.BrowserDownloadURL + ".sha256")
+		if err != nil {
+			return fmt.Errorf("download checksum: %w", err)
+		}
 
-	sum, err := downloadSha256(asset.BrowserDownloadURL + ".sha256")
-	if err != nil {
-		return fmt.Errorf("download checksum: %w", err)
-	}
+		if err := verifySha256(binPath, sum); err != nil {
+			return fmt.Errorf("checksum mismatch: %w", err)
+		}
 
-	if err := verifySha256(binPath, sum); err != nil {
-		return fmt.Errorf("checksum mismatch: %w", err)
-	}
+		if err := installBinary(binPath, exePath); err != nil {
+			return fmt.Errorf("install: %w", err)
+		}
 
-	if err := installBinary(binPath, exePath); err != nil {
-		return fmt.Errorf("install: %w", err)
-	}
+		fmt.Printf("Upgraded %s -> %s\n", Version, rel.TagName)
+		fmt.Printf("Release notes: %s\n", rel.HTMLURL)
 
-	fmt.Printf("Upgraded %s -> %s\n", Version, rel.TagName)
-	fmt.Printf("Release notes: %s\n", rel.HTMLURL)
+		restartDaemonAfterUpgrade(exePath)
+	}
 
-	restartDaemonAfterUpgrade(exePath)
-	return nil
+	return refreshSkillIfInstalled()
 }
 
 // stopDaemonForUpgrade asks the live runner to shut down over IPC so the

upgrade_test.go

@@ -1,8 +1,11 @@
 package main
 
 import (
+	"net/http"
+	"net/http/httptest"
 	"os"
 	"path/filepath"
+	"strings"
 	"testing"
 )
 
@@ -34,3 +37,140 @@ func TestIsRunnerSupervisedNoUnit(t *testing.T) {
 		t.Skip("runner is currently supervised in this environment")
 	}
 }
+
+func TestUpgradeRefreshesInstalledSkill(t *testing.T) {
+	home := isolatedUpgradeHome(t)
+	skillDir := filepath.Join(home, ".gander", "skill")
+	if err := os.MkdirAll(skillDir, 0700); err != nil {
+		t.Fatal(err)
+	}
+	if err := os.WriteFile(filepath.Join(skillDir, "SKILL.md"), []byte("# old\n"), 0644); err != nil {
+		t.Fatal(err)
+	}
+	serveSkillArchive(t, map[string]string{
+		"gander-skill-main/SKILL.md": "# new\n",
+	})
+	stubUpgradeAlreadyCurrent(t, "v9.9.9")
+
+	if err := runUpgrade(); err != nil {
+		t.Fatalf("runUpgrade: %v", err)
+	}
+	body, err := os.ReadFile(filepath.Join(skillDir, "SKILL.md"))
+	if err != nil {
+		t.Fatal(err)
+	}
+	if string(body) != "# new\n" {
+		t.Errorf("SKILL.md = %q, want refreshed copy", body)
+	}
+	for _, dest := range skillDestPaths(home) {
+		assertSkillLinked(t, dest, skillDir)
+	}
+}
+
+func TestUpgradeRefreshesSkillFromDestSymlink(t *testing.T) {
+	home := isolatedUpgradeHome(t)
+	skillDir := filepath.Join(home, ".gander", "skill")
+	dest := filepath.Join(home, ".claude", "skills", "gander")
+	if err := os.MkdirAll(filepath.Dir(dest), 0755); err != nil {
+		t.Fatal(err)
+	}
+	if err := os.Symlink(skillDir, dest); err != nil {
+		t.Fatal(err)
+	}
+	serveSkillArchive(t, map[string]string{
+		"gander-skill-main/SKILL.md": "# from dest\n",
+	})
+	stubUpgradeAlreadyCurrent(t, "v9.9.9")
+
+	if err := runUpgrade(); err != nil {
+		t.Fatalf("runUpgrade: %v", err)
+	}
+	body, err := os.ReadFile(filepath.Join(skillDir, "SKILL.md"))
+	if err != nil {
+		t.Fatal(err)
+	}
+	if string(body) != "# from dest\n" {
+		t.Errorf("SKILL.md = %q, want dest-triggered refresh", body)
+	}
+}
+
+func TestUpgradeSkipsSkillWhenNotInstalled(t *testing.T) {
+	home := isolatedUpgradeHome(t)
+	hit := false
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		hit = true
+		http.Error(w, "should not download skill", http.StatusInternalServerError)
+	}))
+	t.Cleanup(srv.Close)
+	prev := skillDownloadURL
+	skillDownloadURL = srv.URL
+	t.Cleanup(func() { skillDownloadURL = prev })
+	stubUpgradeAlreadyCurrent(t, "v9.9.9")
+
+	if err := runUpgrade(); err != nil {
+		t.Fatalf("runUpgrade: %v", err)
+	}
+	if hit {
+		t.Error("skill download ran even though skill was not installed")
+	}
+	for _, dest := range skillDestPaths(home) {
+		if _, err := os.Lstat(dest); !os.IsNotExist(err) {
+			t.Errorf("created dest %s: %v", dest, err)
+		}
+	}
+}
+
+func TestUpgradeSkillFailureDoesNotUndoCLI(t *testing.T) {
+	home := isolatedUpgradeHome(t)
+	skillDir := filepath.Join(home, ".gander", "skill")
+	if err := os.MkdirAll(skillDir, 0700); err != nil {
+		t.Fatal(err)
+	}
+	if err := os.WriteFile(filepath.Join(skillDir, "SKILL.md"), []byte("# old\n"), 0644); err != nil {
+		t.Fatal(err)
+	}
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		http.Error(w, "boom", http.StatusInternalServerError)
+	}))
+	t.Cleanup(srv.Close)
+	prev := skillDownloadURL
+	skillDownloadURL = srv.URL
+	t.Cleanup(func() { skillDownloadURL = prev })
+	stubUpgradeAlreadyCurrent(t, "v9.9.9")
+
+	err := runUpgrade()
+	if err == nil {
+		t.Fatal("expected skill error")
+	}
+	if !strings.Contains(err.Error(), "skill:") {
+		t.Errorf("err = %v, want wrapped skill: prefix", err)
+	}
+	body, readErr := os.ReadFile(filepath.Join(skillDir, "SKILL.md"))
+	if readErr != nil {
+		t.Fatal(readErr)
+	}
+	if string(body) != "# old\n" {
+		t.Errorf("SKILL.md replaced after failed download: %q", body)
+	}
+}
+
+func isolatedUpgradeHome(t *testing.T) string {
+	t.Helper()
+	home := t.TempDir()
+	t.Setenv("HOME", home)
+	t.Setenv("GANDER_CONFIG", "")
+	return home
+}
+
+func stubUpgradeAlreadyCurrent(t *testing.T, version string) {
+	t.Helper()
+	prevV := Version
+	Version = version
+	t.Cleanup(func() { Version = prevV })
+
+	prevFetch := fetchLatestRelease
+	fetchLatestRelease = func() (*releaseInfo, error) {
+		return &releaseInfo{TagName: version}, nil
+	}
+	t.Cleanup(func() { fetchLatestRelease = prevFetch })
+}