feat(agent): inject TTS [[tts]] directive guidance when auto mode is "tagged"

- Add TTSAutoMode field to LoopConfig, Loop, SystemPromptConfig
- Wire from config.Tts.Auto through resolver to system prompt
- Inject "## Voice Response" section explaining [[tts]] usage
- Update AGENTS.md: voice only when user explicitly requests

cmd/gateway_managed.go

@@ -235,6 +235,7 @@ func wireExtras(
 		SkillTenantCfgs:        stores.SkillTenantCfgs,
 		SystemConfigs:          stores.SystemConfigs,
 		Workspace:              workspace,
+		TTSAutoMode:            appCfg.Tts.Auto,
 		AutoInjector:           autoInjector,
 		EvolutionMetricsStore:  stores.EvolutionMetrics,
 		DomainBus:              domainBus,

internal/agent/loop_history.go

@@ -231,6 +231,7 @@ func (l *Loop) buildMessages(ctx context.Context, history []providers.Message, s
 		SandboxWorkspaceAccess: l.sandboxWorkspaceAccess,
 		ShellDenyGroups:        l.shellDenyGroups,
 		SelfEvolve:             l.selfEvolve,
+		TTSAutoMode:            l.ttsAutoMode,
 		ProviderType:           providerTypeOf(l.provider),
 		CredentialCLIContext:   l.buildCredentialCLIContext(ctx),
 		IsBootstrap:            hadBootstrap && l.agentType != store.AgentTypePredefined,

internal/agent/loop_types.go

@@ -200,6 +200,9 @@ type Loop struct {
 	// Self-evolve: predefined agents can update SOUL.md through chat
 	selfEvolve bool
 
+	// TTS auto mode from config: "off", "always", "inbound", "tagged"
+	ttsAutoMode string
+
 	// Skill learning loop: when skillEvolve=true, the loop injects nudges reminding
 	// the agent to capture reusable patterns as skills via skill_manage.
 	skillEvolve        bool
@@ -388,6 +391,10 @@ type LoopConfig struct {
 	// Self-evolve: predefined agents can update SOUL.md (style/tone) through chat
 	SelfEvolve bool
 
+	// TTS auto mode from config: "off", "always", "inbound", "tagged"
+	// When "tagged", inject [[tts]] directive guidance into system prompt.
+	TTSAutoMode string
+
 	// Skill evolution: agent learning loop config (from other_config JSONB)
 	SkillEvolve        bool
 	SkillNudgeInterval int // 0 = disabled, 15 = default
@@ -529,6 +536,7 @@ func NewLoop(cfg LoopConfig) *Loop {
 		promptMode:             cfg.PromptMode,
 		pinnedSkills:           cfg.PinnedSkills,
 		selfEvolve:             cfg.SelfEvolve,
+		ttsAutoMode:            cfg.TTSAutoMode,
 		skillEvolve:            cfg.SkillEvolve,
 		skillNudgeInterval:     cfg.SkillNudgeInterval,
 		isTeamLead:             cfg.IsTeamLead,

internal/agent/resolver.go

@@ -120,6 +120,9 @@ type ResolverDeps struct {
 	// Global workspace root (GOCLAW_WORKSPACE)
 	Workspace string
 
+	// TTS auto mode from config: "off", "always", "inbound", "tagged"
+	TTSAutoMode string
+
 	// V3 auto-inject: episodic memory injection into system prompt (nil = disabled)
 	AutoInjector memory.AutoInjector
 
@@ -511,6 +514,7 @@ func NewManagedResolver(deps ResolverDeps) ResolverFunc {
 			PromptMode:             PromptMode(ag.ParsePromptMode()),
 			PinnedSkills:           ag.ParsePinnedSkills(),
 			SelfEvolve:             ag.ParseSelfEvolve(),
+			TTSAutoMode:            deps.TTSAutoMode,
 			SkillEvolve:            ag.AgentType == store.AgentTypePredefined && ag.ParseSkillEvolve(),
 			SkillNudgeInterval:     ag.ParseSkillNudgeInterval(),
 			WorkspaceSharing:       ag.ParseWorkspaceSharing(),

internal/agent/systemprompt.go

@@ -135,6 +135,10 @@ type SystemPromptConfig struct {
 	// Self-evolution: predefined agents can update SOUL.md (style/tone)
 	SelfEvolve bool
 
+	// TTSAutoMode: "off", "always", "inbound", "tagged". When "tagged", inject
+	// [[tts]] directive guidance so the agent knows how to trigger voice responses.
+	TTSAutoMode string
+
 	// ShellDenyGroups holds effective deny group overrides for this agent.
 	// nil = all defaults. Used to adapt system prompt instructions.
 	ShellDenyGroups map[string]bool
@@ -327,6 +331,11 @@ func BuildSystemPrompt(cfg SystemPromptConfig) string {
 		lines = append(lines, cfg.CredentialCLIContext, "")
 	}
 
+	// 2.6. ## Voice Response — inject when TTS auto mode is "tagged"
+	if (isFull || isTask) && !cfg.IsBootstrap && cfg.TTSAutoMode == "tagged" {
+		lines = append(lines, buildVoiceResponseSection()...)
+	}
+
 	// 3. ## Safety — task/none get slim version (keeps prompt injection defense)
 	if isTask || isNone {
 		lines = append(lines, buildSafetySlimSection()...)

internal/agent/systemprompt_sections.go

@@ -729,3 +729,22 @@ func buildTeamMembersSection(members []store.TeamMemberData, teamGuidance string
 	lines = append(lines, "")
 	return lines
 }
+
+// buildVoiceResponseSection generates guidance for triggering auto TTS in "tagged" mode.
+// When TTS auto mode is "tagged", agent responses containing [[tts]] are converted to voice.
+func buildVoiceResponseSection() []string {
+	return []string{
+		"## Voice Response",
+		"",
+		"You can respond with voice/audio by wrapping text with `[[tts]]`:",
+		"",
+		"```",
+		"[[tts]]This text will be spoken aloud.[[/tts]]",
+		"```",
+		"",
+		"**ONLY use [[tts]] when the user explicitly asks for voice/audio response.**",
+		"Examples: \"read this aloud\", \"respond with voice\", \"speak this\", \"tell me a story (voice)\".",
+		"Do NOT add [[tts]] just because you think it would be nice — text is the default.",
+		"",
+	}
+}

internal/bootstrap/templates/AGENTS.md

@@ -113,4 +113,4 @@ Tips:
 
 ## Voice
 
-If you have TTS capability, use voice for stories and "storytime" moments — more engaging than walls of text.
+If you have TTS capability, only use voice when the user explicitly asks for it (e.g. "read aloud", "respond with voice", "tell me a story in voice").