fix github blob skill URL installs and metadata links

pkg/skills/github_registry.go

@@ -93,7 +93,11 @@ func (r *GitHubRegistry) SkillURL(target, version string) string {
 		return fmt.Sprintf("%s/%s", base, urlPath)
 	}
 	if ref.SubPath != "" {
-		return fmt.Sprintf("%s/%s/tree/%s/%s", base, urlPath, ref.Ref, ref.SubPath)
+		viewKind := "tree"
+		if isSkillMarkdownPath(ref.SubPath) {
+			viewKind = "blob"
+		}
+		return fmt.Sprintf("%s/%s/%s/%s/%s", base, urlPath, viewKind, ref.Ref, ref.SubPath)
 	}
 	if ref.Ref != "main" {
 		return fmt.Sprintf("%s/%s/tree/%s", base, urlPath, ref.Ref)

pkg/skills/github_registry_test.go

@@ -176,6 +176,11 @@ func TestGitHubRegistrySkillURLUsesProvidedVersionAndBasePath(t *testing.T) {
 		"https://ghe.example.com/git/org/repo/tree/feature/skills-registry/skills/pr-review",
 		registry.SkillURL("org/repo/skills/pr-review", "feature/skills-registry"),
 	)
+	assert.Equal(
+		t,
+		"https://ghe.example.com/git/org/repo/blob/main/.agents/skills/pr-review/SKILL.md",
+		registry.SkillURL("https://ghe.example.com/git/org/repo/blob/main/.agents/skills/pr-review/SKILL.md", ""),
+	)
 }
 
 func TestGitHubRegistryResolveInstallDirNameSupportsFullURLs(t *testing.T) {

pkg/skills/installer.go

@@ -217,7 +217,7 @@ func looksLikeSkillSubPath(subPath string) bool {
 	if subPath == "" {
 		return false
 	}
-	if subPath == "SKILL.md" || strings.HasSuffix(subPath, "/SKILL.md") {
+	if isSkillMarkdownPath(subPath) {
 		return true
 	}
 	parts := strings.Split(subPath, "/")
@@ -230,6 +230,11 @@ func looksLikeSkillSubPath(subPath string) bool {
 	return false
 }
 
+func isSkillMarkdownPath(subPath string) bool {
+	subPath = strings.Trim(strings.TrimSpace(subPath), "/")
+	return subPath == "SKILL.md" || strings.HasSuffix(subPath, "/SKILL.md")
+}
+
 // parseGitHubRef parses a GitHub reference.
 // Supports: "owner/repo", "owner/repo/path", or full URL like "https://github.com/owner/repo/tree/ref/path"
 func parseGitHubRef(repo string) (GitHubRef, error) {
@@ -462,8 +467,12 @@ func (si *SkillInstaller) getGithubDirAllFiles(ctx context.Context, apiURL, loca
 func (si *SkillInstaller) downloadRaw(ctx context.Context, owner, repo, ref, subPath, localDir string) error {
 	urlPath := path.Join(owner, repo, ref)
 	if subPath != "" {
+		if isSkillMarkdownPath(subPath) {
+			urlPath = strings.TrimSuffix(path.Join(urlPath, subPath), "/SKILL.md")
+		} else {
 			urlPath = path.Join(urlPath, subPath)
 		}
+	}
 	url := fmt.Sprintf("%s/%s/SKILL.md", si.githubRawBaseURL, urlPath)
 
 	req, err := http.NewRequestWithContext(ctx, "GET", url, nil)

pkg/skills/installer_test.go

@@ -231,6 +231,50 @@ func TestSkillInstallerResolveGitHubRefUsesDefaultBranch(t *testing.T) {
 	}
 }
 
+func TestSkillInstallerInstallFromGitHubToDirSupportsBlobSkillURL(t *testing.T) {
+	tmpDir := t.TempDir()
+	var server *httptest.Server
+	server = httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		switch r.URL.Path {
+		case "/api/v3/repos/org/repo/contents/.agents/skills/pr-review/SKILL.md":
+			w.Header().Set("Content-Type", "application/json")
+			_, _ = w.Write([]byte(`{"type":"file","name":"SKILL.md"}`))
+		case "/raw/org/repo/main/.agents/skills/pr-review/SKILL.md":
+			_, _ = w.Write([]byte("---\nname: pr-review\ndescription: PR review skill\n---\n# PR Review\n"))
+		default:
+			t.Fatalf("unexpected path: %s", r.URL.Path)
+		}
+	}))
+	defer server.Close()
+
+	installer, err := NewSkillInstallerWithBaseURL(tmpDir, server.URL, "", "")
+	if err != nil {
+		t.Fatalf("NewSkillInstallerWithBaseURL() error = %v", err)
+	}
+
+	targetDir := filepath.Join(tmpDir, "skills", "pr-review")
+	result, err := installer.InstallFromGitHubToDir(
+		context.Background(),
+		server.URL+"/org/repo/blob/main/.agents/skills/pr-review/SKILL.md",
+		"",
+		targetDir,
+	)
+	if err != nil {
+		t.Fatalf("InstallFromGitHubToDir() error = %v", err)
+	}
+	if result.Version != "main" {
+		t.Fatalf("version = %q, want main", result.Version)
+	}
+
+	content, err := os.ReadFile(filepath.Join(targetDir, "SKILL.md"))
+	if err != nil {
+		t.Fatalf("ReadFile(SKILL.md) error = %v", err)
+	}
+	if !strings.Contains(string(content), "name: pr-review") {
+		t.Fatalf("SKILL.md content = %q, want skill metadata", string(content))
+	}
+}
+
 func TestShouldDownload(t *testing.T) {
 	tests := []struct {
 		name string