test(agent): fix ContinuityKeepCount; refactor(skills): YAML-only frontmatter

pkg/agent/loop_test.go

@@ -87,25 +87,25 @@ func TestContinuityKeepCount_UsesConfiguredPolicy(t *testing.T) {
 	cfg := config.DefaultConfig()
 	cfg.Agents.Defaults.ContinuityRetention.MinMessages = 3
 	cfg.Agents.Defaults.ContinuityRetention.MaxMessages = 7
-	cfg.Agents.Defaults.ContinuityRetention.TargetContextRatio = 0.01
+	cfg.Agents.Defaults.ContinuityRetention.TargetContextRatio = 0.5 // 50% of context window
 
 	al := &AgentLoop{
 		cfg:           cfg,
-		contextWindow: 256,
+		contextWindow: 10000, // Large enough to hold many messages
 	}
 
-	// Large history should be limited by MaxMessages
+	// Large history should be limited by MaxMessages when token budget allows
 	largeHistory := buildHistory(100, "test content")
 	keep := al.continuityKeepCount(largeHistory)
 	if keep != 7 {
 		t.Errorf("expected keep=7 for large history, got %d", keep)
 	}
 
-	// Small history with low token count should use MinMessages
-	smallHistory := buildHistory(5, "x") // Very short content
+	// Small history should use actual count when under MinMessages
+	smallHistory := buildHistory(2, "x") // Under MinMessages
 	keep = al.continuityKeepCount(smallHistory)
-	if keep != 3 {
-		t.Errorf("expected keep=3 for small history, got %d", keep)
+	if keep != 2 { // Should keep actual count when under min
+		t.Errorf("expected keep=2 for small history, got %d", keep)
 	}
 }
 

pkg/skills/graph_test.go

@@ -355,12 +355,16 @@ Content.
 	assert.Nil(t, g.GetIndex())
 }
 
-func TestExtendedFrontmatter_JSON(t *testing.T) {
+func TestExtendedFrontmatter_YAML(t *testing.T) {
 	t.Parallel()
 	tmp := t.TempDir()
 
-	writeSkill(t, tmp, "json-skill", `---
-{"name":"json-skill","description":"A JSON frontmatter skill","tags":["alpha","beta"],"domain":"testing","is_moc":true}
+	writeSkill(t, tmp, "yaml-skill", `---
+name: yaml-skill
+description: A YAML frontmatter skill
+tags: alpha, beta
+domain: testing
+is_moc: true
 ---
 Content with [[some-link]].
 `)
@@ -370,7 +374,7 @@ Content with [[some-link]].
 	require.Len(t, skills, 1)
 
 	s := skills[0]
-	assert.Empty(t, cmp.Diff("json-skill", s.Name))
+	assert.Empty(t, cmp.Diff("yaml-skill", s.Name))
 	assert.Empty(t, cmp.Diff([]string{"alpha", "beta"}, s.Tags))
 	assert.Empty(t, cmp.Diff("testing", s.Domain))
 }

pkg/skills/loader.go

@@ -9,8 +9,6 @@ import (
 	"regexp"
 	"strings"
 	"time"
-
-	jsonv2 "github.com/go-json-experiment/json"
 )
 
 var namePattern = regexp.MustCompile(`^[a-zA-Z0-9]+(-[a-zA-Z0-9]+)*$`)
@@ -315,13 +313,6 @@ func (sl *SkillsLoader) getSkillMetadata(skillPath string) *SkillMetadata {
 		}
 	}
 
-	// Try JSON first (for backward compatibility)
-	var jsonMeta SkillMetadata
-	if err := jsonv2.Unmarshal([]byte(frontmatter), &jsonMeta); err == nil && jsonMeta.Name != "" {
-		return &jsonMeta
-	}
-
-	// Fall back to simple YAML parsing
 	yamlMeta := sl.parseSimpleYAML(frontmatter)
 	meta := &SkillMetadata{
 		Name:        yamlMeta["name"],