diff --git a/packages/opencode/src/app/app.ts b/packages/opencode/src/app/app.ts
index fc7f49cb951..459785de87e 100644
--- a/packages/opencode/src/app/app.ts
+++ b/packages/opencode/src/app/app.ts
@@ -20,6 +20,7 @@ export namespace App {
         root: z.string(),
         cwd: z.string(),
         state: z.string(),
+        promptHistory: z.string(),
       }),
       time: z.object({
         initialized: z.number().optional(),
@@ -80,6 +81,7 @@ export namespace App {
         data,
         root,
         cwd: input.cwd,
+        promptHistory: path.join(data, "prompt-history"),
       },
     }
     const app = {
diff --git a/packages/sdk/go/app.go b/packages/sdk/go/app.go
index 36d5be77fbf..1f22efac689 100644
--- a/packages/sdk/go/app.go
+++ b/packages/sdk/go/app.go
@@ -248,23 +248,25 @@ func (r appJSON) RawJSON() string {
 }
 
 type AppPath struct {
-	Config string      `json:"config,required"`
-	Cwd    string      `json:"cwd,required"`
-	Data   string      `json:"data,required"`
-	Root   string      `json:"root,required"`
-	State  string      `json:"state,required"`
-	JSON   appPathJSON `json:"-"`
+	Config        string      `json:"config,required"`
+	Cwd           string      `json:"cwd,required"`
+	Data          string      `json:"data,required"`
+	Root          string      `json:"root,required"`
+	State         string      `json:"state,required"`
+	PromptHistory string      `json:"promptHistory,required"`
+	JSON          appPathJSON `json:"-"`
 }
 
 // appPathJSON contains the JSON metadata for the struct [AppPath]
 type appPathJSON struct {
-	Config      apijson.Field
-	Cwd         apijson.Field
-	Data        apijson.Field
-	Root        apijson.Field
-	State       apijson.Field
-	raw         string
-	ExtraFields map[string]apijson.Field
+	Config        apijson.Field
+	Cwd           apijson.Field
+	Data          apijson.Field
+	Root          apijson.Field
+	State         apijson.Field
+	PromptHistory apijson.Field
+	raw           string
+	ExtraFields   map[string]apijson.Field
 }
 
 func (r *AppPath) UnmarshalJSON(data []byte) (err error) {
diff --git a/packages/tui/internal/app/app.go b/packages/tui/internal/app/app.go
index af8157adcde..232dce2ebef 100644
--- a/packages/tui/internal/app/app.go
+++ b/packages/tui/internal/app/app.go
@@ -32,6 +32,7 @@ type App struct {
 	Providers         []opencode.Provider
 	Version           string
 	StatePath         string
+	PromptHistoryPath string
 	Config            *opencode.Config
 	Client            *opencode.Client
 	State             *State
@@ -124,6 +125,14 @@ func New(
 		SaveState(appStatePath, appState)
 	}
 
+	// Load project-specific prompt history
+	promptHistoryPath := appInfo.Path.PromptHistory
+	promptHistory, err := LoadPromptHistory(promptHistoryPath)
+	if err != nil {
+		promptHistory = make([]Prompt, 0)
+	}
+	appState.MessageHistory = promptHistory
+
 	if appState.AgentModel == nil {
 		appState.AgentModel = make(map[string]AgentModel)
 	}
@@ -184,22 +193,23 @@ func New(
 	slog.Debug("Loaded config", "config", configInfo)
 
 	app := &App{
-		Info:           appInfo,
-		Agents:         agents,
-		Version:        version,
-		StatePath:      appStatePath,
-		Config:         configInfo,
-		State:          appState,
-		Client:         httpClient,
-		AgentIndex:     agentIndex,
-		Session:        &opencode.Session{},
-		Messages:       []Message{},
-		Commands:       commands.LoadFromConfig(configInfo),
-		InitialModel:   initialModel,
-		InitialPrompt:  initialPrompt,
-		InitialAgent:   initialAgent,
-		InitialSession: initialSession,
-		ScrollSpeed:    int(configInfo.Tui.ScrollSpeed),
+		Info:              appInfo,
+		Agents:            agents,
+		Version:           version,
+		StatePath:         appStatePath,
+		PromptHistoryPath: appInfo.Path.PromptHistory,
+		Config:            configInfo,
+		State:             appState,
+		Client:            httpClient,
+		AgentIndex:        agentIndex,
+		Session:           &opencode.Session{},
+		Messages:          []Message{},
+		Commands:          commands.LoadFromConfig(configInfo),
+		InitialModel:      initialModel,
+		InitialPrompt:     initialPrompt,
+		InitialAgent:      initialAgent,
+		InitialSession:    initialSession,
+		ScrollSpeed:       int(configInfo.Tui.ScrollSpeed),
 	}
 
 	return app, nil
@@ -671,10 +681,20 @@ func (a *App) HasAnimatingWork() bool {
 
 func (a *App) SaveState() tea.Cmd {
 	return func() tea.Msg {
-		err := SaveState(a.StatePath, a.State)
+		// Save main state (without prompt history)
+		stateToSave := *a.State
+		stateToSave.MessageHistory = make([]Prompt, 0) // Don't save prompt history in main state
+		err := SaveState(a.StatePath, &stateToSave)
 		if err != nil {
 			slog.Error("Failed to save state", "error", err)
 		}
+
+		// Save prompt history separately
+		err = SavePromptHistory(a.PromptHistoryPath, a.State.MessageHistory)
+		if err != nil {
+			slog.Error("Failed to save prompt history", "error", err)
+		}
+
 		return nil
 	}
 }
diff --git a/packages/tui/internal/app/state.go b/packages/tui/internal/app/state.go
index cc65eea5eee..736eec5e73c 100644
--- a/packages/tui/internal/app/state.go
+++ b/packages/tui/internal/app/state.go
@@ -172,3 +172,37 @@ func LoadState(filePath string) (*State, error) {
 
 	return &state, nil
 }
+
+// LoadPromptHistory loads prompt history from a separate project-specific file
+func LoadPromptHistory(filePath string) ([]Prompt, error) {
+	var history struct {
+		MessageHistory []Prompt `toml:"message_history"`
+	}
+	if _, err := toml.DecodeFile(filePath, &history); err != nil {
+		return make([]Prompt, 0), nil // Return empty on any error
+	}
+	for _, prompt := range history.MessageHistory {
+		for _, att := range prompt.Attachments {
+			att.RestoreSourceType()
+		}
+	}
+	return history.MessageHistory, nil
+}
+
+// SavePromptHistory saves prompt history to a separate project-specific file
+func SavePromptHistory(filePath string, history []Prompt) error {
+	file, err := os.Create(filePath)
+	if err != nil {
+		return err
+	}
+	defer file.Close()
+
+	writer := bufio.NewWriter(file)
+	err = toml.NewEncoder(writer).Encode(struct {
+		MessageHistory []Prompt `toml:"message_history"`
+	}{history})
+	if err != nil {
+		return err
+	}
+	return writer.Flush()
+}