diff --git a/pkg/skills/github_registry.go b/pkg/skills/github_registry.go
index 59f7d4fd7..25beca5d7 100644
--- a/pkg/skills/github_registry.go
+++ b/pkg/skills/github_registry.go
@@ -73,6 +73,14 @@ func (r *GitHubRegistry) ResolveInstallDirName(target string) (string, error) {
 	return githubInstallDirNameWithBaseURL(target, r.webBase)
 }
 
+func (r *GitHubRegistry) NormalizeInstallTarget(target string) string {
+	normalized, err := canonicalGitHubRegistrySlugWithBaseURL(target, r.webBase)
+	if err != nil {
+		return target
+	}
+	return normalized
+}
+
 func (r *GitHubRegistry) SkillURL(target, version string) string {
 	defaultRef := strings.TrimSpace(version)
 	ref, err := parseGitHubRefWithBaseURL(target, r.webBase, defaultRef)
diff --git a/pkg/skills/registry.go b/pkg/skills/registry.go
index 871c10226..6c8e28a4e 100644
--- a/pkg/skills/registry.go
+++ b/pkg/skills/registry.go
@@ -73,6 +73,27 @@ type SkillRegistry interface {
 	DownloadAndInstall(ctx context.Context, slug, version, targetDir string) (*InstallResult, error)
 }
 
+// InstallTargetNormalizer is implemented by registries that can canonicalize
+// user-provided install targets into a stable slug for origin metadata.
+type InstallTargetNormalizer interface {
+	NormalizeInstallTarget(target string) string
+}
+
+func NormalizeInstallTargetForRegistryInstance(registry SkillRegistry, target string) string {
+	if registry == nil || target == "" {
+		return target
+	}
+	normalizer, ok := registry.(InstallTargetNormalizer)
+	if !ok {
+		return target
+	}
+	normalized := normalizer.NormalizeInstallTarget(target)
+	if normalized == "" {
+		return target
+	}
+	return normalized
+}
+
 // RegistryConfig holds configuration for all skill registries.
 // This is the input to NewRegistryManagerFromConfig.
 type RegistryConfig struct {
diff --git a/pkg/tools/skills_install.go b/pkg/tools/skills_install.go
index e73692fc2..c7db02eb3 100644
--- a/pkg/tools/skills_install.go
+++ b/pkg/tools/skills_install.go
@@ -198,18 +198,19 @@ type originMeta struct {
 }
 
 func writeOriginMeta(targetDir string, registry skills.SkillRegistry, slug, version string) error {
+	normalizedSlug := skills.NormalizeInstallTargetForRegistryInstance(registry, slug)
 	registryName := ""
 	registryURL := ""
 	if registry != nil {
 		registryName = registry.Name()
-		registryURL = registry.SkillURL(slug, version)
+		registryURL = registry.SkillURL(normalizedSlug, version)
 	}
 
 	meta := originMeta{
 		Version:          1,
 		OriginKind:       "third_party",
 		Registry:         registryName,
-		Slug:             slug,
+		Slug:             normalizedSlug,
 		RegistryURL:      registryURL,
 		InstalledVersion: version,
 		InstalledAt:      time.Now().UnixMilli(),
diff --git a/pkg/tools/skills_install_test.go b/pkg/tools/skills_install_test.go
index fdf42f11d..9ecf34ea3 100644
--- a/pkg/tools/skills_install_test.go
+++ b/pkg/tools/skills_install_test.go
@@ -67,6 +67,19 @@ func (m *mockGitHubInstallRegistry) DownloadAndInstall(
 	return &skills.InstallResult{Version: "main"}, nil
 }
 
+type stubGitHubInstallRegistry struct {
+	*skills.GitHubRegistry
+}
+
+func (m *stubGitHubInstallRegistry) DownloadAndInstall(
+	context.Context,
+	string,
+	string,
+	string,
+) (*skills.InstallResult, error) {
+	return &skills.InstallResult{Version: "main"}, nil
+}
+
 func TestInstallSkillToolName(t *testing.T) {
 	tool := NewInstallSkillTool(skills.NewRegistryManager(), t.TempDir())
 	assert.Equal(t, "install_skill", tool.Name())
@@ -166,8 +179,12 @@ func TestInstallSkillToolMissingRegistry(t *testing.T) {
 }
 
 func TestInstallSkillToolAllowsGitHubURLSlug(t *testing.T) {
+	registry := skills.GitHubRegistryConfig{Enabled: true, BaseURL: "https://github.com"}.BuildRegistry()
+	githubRegistry, ok := registry.(*skills.GitHubRegistry)
+	require.True(t, ok)
+
 	registryMgr := skills.NewRegistryManager()
-	registryMgr.AddRegistry(&mockGitHubInstallRegistry{})
+	registryMgr.AddRegistry(&stubGitHubInstallRegistry{GitHubRegistry: githubRegistry})
 	workspace := t.TempDir()
 	tool := NewInstallSkillTool(registryMgr, workspace)
 
@@ -187,7 +204,7 @@ func TestInstallSkillToolAllowsGitHubURLSlug(t *testing.T) {
 	require.NoError(t, json.Unmarshal(data, &meta))
 	assert.Equal(t, "third_party", meta.OriginKind)
 	assert.Equal(t, "github", meta.Registry)
-	assert.Equal(t, slug, meta.Slug)
+	assert.Equal(t, "synthetic-lab/octofriend/.agents/skills/pr-review", meta.Slug)
 	assert.Equal(t, slug, meta.RegistryURL)
 	assert.Equal(t, "main", meta.InstalledVersion)
 	assert.NotZero(t, meta.InstalledAt)