todo: include full state and reminder in all tool responses

Add AllTodos field to CreateTodoOutput, CreateTodosOutput, and
UpdateTodosOutput so every response includes the complete current
state of all todo items. This gives the LLM full visibility into
the todo list without needing a separate list_todos call.

Also removes the auto-clear-on-all-completed behavior so that
completed items remain visible, and adds CreateTodoOutput as a
dedicated output type for create_todo (replacing bare Todo).

Author: Gordon

pkg/tools/builtin/todo.go

@@ -54,13 +54,22 @@ type UpdateTodosArgs struct {
 
 // Output types for JSON-structured responses.
 
+type CreateTodoOutput struct {
+	Created  Todo   `json:"created" jsonschema:"The created todo item"`
+	AllTodos []Todo `json:"all_todos" jsonschema:"Current state of all todo items"`
+	Reminder string `json:"reminder,omitempty" jsonschema:"Reminder about incomplete todos that still need to be completed"`
+}
+
 type CreateTodosOutput struct {
-	Created []Todo `json:"created" jsonschema:"List of created todo items"`
+	Created  []Todo `json:"created" jsonschema:"List of created todo items"`
+	AllTodos []Todo `json:"all_todos" jsonschema:"Current state of all todo items"`
+	Reminder string `json:"reminder,omitempty" jsonschema:"Reminder about incomplete todos that still need to be completed"`
 }
 
 type UpdateTodosOutput struct {
 	Updated  []TodoUpdate `json:"updated,omitempty" jsonschema:"List of successfully updated todos"`
 	NotFound []string     `json:"not_found,omitempty" jsonschema:"IDs of todos that were not found"`
+	AllTodos []Todo       `json:"all_todos" jsonschema:"Current state of all todo items"`
 	Reminder string       `json:"reminder,omitempty" jsonschema:"Reminder about incomplete todos that still need to be completed"`
 }
 
@@ -202,15 +211,24 @@ func (h *todoHandler) jsonResult(v any) (*tools.ToolCallResult, error) {
 }
 
 func (h *todoHandler) createTodo(_ context.Context, params CreateTodoArgs) (*tools.ToolCallResult, error) {
-	return h.jsonResult(h.addTodo(params.Description))
+	created := h.addTodo(params.Description)
+	return h.jsonResult(CreateTodoOutput{
+		Created:  created,
+		AllTodos: h.storage.All(),
+		Reminder: h.incompleteReminder(),
+	})
 }
 
 func (h *todoHandler) createTodos(_ context.Context, params CreateTodosArgs) (*tools.ToolCallResult, error) {
 	created := make([]Todo, 0, len(params.Descriptions))
 	for _, desc := range params.Descriptions {
 		created = append(created, h.addTodo(desc))
 	}
-	return h.jsonResult(CreateTodosOutput{Created: created})
+	return h.jsonResult(CreateTodosOutput{
+		Created:  created,
+		AllTodos: h.storage.All(),
+		Reminder: h.incompleteReminder(),
+	})
 }
 
 func (h *todoHandler) updateTodos(_ context.Context, params UpdateTodosArgs) (*tools.ToolCallResult, error) {
@@ -239,28 +257,12 @@ func (h *todoHandler) updateTodos(_ context.Context, params UpdateTodosArgs) (*t
 		return res, nil
 	}
 
-	if h.allCompleted() {
-		h.storage.Clear()
-	} else {
-		result.Reminder = h.incompleteReminder()
-	}
+	result.AllTodos = h.storage.All()
+	result.Reminder = h.incompleteReminder()
 
 	return h.jsonResult(result)
 }
 
-func (h *todoHandler) allCompleted() bool {
-	all := h.storage.All()
-	if len(all) == 0 {
-		return false
-	}
-	for _, todo := range all {
-		if todo.Status != "completed" {
-			return false
-		}
-	}
-	return true
-}
-
 // incompleteReminder returns a reminder string listing any non-completed todos,
 // or an empty string if all are completed (or storage is empty).
 func (h *todoHandler) incompleteReminder() string {
@@ -306,7 +308,7 @@ func (t *TodoTool) Tools(context.Context) ([]tools.Tool, error) {
 			Category:     "todo",
 			Description:  "Create a new todo item with a description",
 			Parameters:   tools.MustSchemaFor[CreateTodoArgs](),
-			OutputSchema: tools.MustSchemaFor[Todo](),
+			OutputSchema: tools.MustSchemaFor[CreateTodoOutput](),
 			Handler:      tools.NewHandler(t.handler.createTodo),
 			Annotations: tools.ToolAnnotations{
 				Title:        "Create TODO",

pkg/tools/builtin/todo_test.go

@@ -31,11 +31,16 @@ func TestTodoTool_CreateTodo(t *testing.T) {
 	})
 	require.NoError(t, err)
 
-	var output Todo
+	var output CreateTodoOutput
 	require.NoError(t, json.Unmarshal([]byte(result.Output), &output))
-	assert.Equal(t, "todo_1", output.ID)
-	assert.Equal(t, "Test todo item", output.Description)
-	assert.Equal(t, "pending", output.Status)
+	assert.Equal(t, "todo_1", output.Created.ID)
+	assert.Equal(t, "Test todo item", output.Created.Description)
+	assert.Equal(t, "pending", output.Created.Status)
+
+	// Full state is included in the response
+	require.Len(t, output.AllTodos, 1)
+	assert.Equal(t, "todo_1", output.AllTodos[0].ID)
+	assert.Contains(t, output.Reminder, "todo_1")
 
 	require.Equal(t, 1, storage.Len())
 	requireMeta(t, result, 1)
@@ -59,10 +64,16 @@ func TestTodoTool_CreateTodos(t *testing.T) {
 	assert.Equal(t, "todo_2", output.Created[1].ID)
 	assert.Equal(t, "todo_3", output.Created[2].ID)
 
+	// Full state included in response
+	require.Len(t, output.AllTodos, 3)
+	assert.Contains(t, output.Reminder, "todo_1")
+	assert.Contains(t, output.Reminder, "todo_2")
+	assert.Contains(t, output.Reminder, "todo_3")
+
 	assert.Equal(t, 3, storage.Len())
 	requireMeta(t, result, 3)
 
-	// A second call continues the ID sequence
+	// A second call continues the ID sequence and includes all 4 items
 	result, err = tool.handler.createTodos(t.Context(), CreateTodosArgs{
 		Descriptions: []string{"Last"},
 	})
@@ -71,6 +82,7 @@ func TestTodoTool_CreateTodos(t *testing.T) {
 	require.NoError(t, json.Unmarshal([]byte(result.Output), &output))
 	require.Len(t, output.Created, 1)
 	assert.Equal(t, "todo_4", output.Created[0].ID)
+	require.Len(t, output.AllTodos, 4)
 	assert.Equal(t, 4, storage.Len())
 	requireMeta(t, result, 4)
 }
@@ -144,6 +156,12 @@ func TestTodoTool_UpdateTodos(t *testing.T) {
 	assert.Equal(t, "in-progress", output.Updated[1].Status)
 	assert.Empty(t, output.NotFound)
 
+	// Full state included in response
+	require.Len(t, output.AllTodos, 3)
+	assert.Equal(t, "completed", output.AllTodos[0].Status)
+	assert.Equal(t, "pending", output.AllTodos[1].Status)
+	assert.Equal(t, "in-progress", output.AllTodos[2].Status)
+
 	// Reminder should list incomplete todos
 	assert.Contains(t, output.Reminder, "todo_2")
 	assert.Contains(t, output.Reminder, "todo_3")
@@ -212,7 +230,7 @@ func TestTodoTool_UpdateTodos_AllNotFound(t *testing.T) {
 	assert.Equal(t, "nonexistent2", output.NotFound[1])
 }
 
-func TestTodoTool_UpdateTodos_ClearsWhenAllCompleted(t *testing.T) {
+func TestTodoTool_UpdateTodos_AllCompleted_NoAutoRemoval(t *testing.T) {
 	storage := NewMemoryTodoStorage()
 	tool := NewTodoTool(WithStorage(storage))
 
@@ -234,8 +252,14 @@ func TestTodoTool_UpdateTodos_ClearsWhenAllCompleted(t *testing.T) {
 	require.Len(t, output.Updated, 2)
 	assert.Empty(t, output.Reminder) // no reminder when all completed
 
-	assert.Empty(t, storage.All())
-	requireMeta(t, result, 0)
+	// Full state shows both items as completed
+	require.Len(t, output.AllTodos, 2)
+	assert.Equal(t, "completed", output.AllTodos[0].Status)
+	assert.Equal(t, "completed", output.AllTodos[1].Status)
+
+	// Todos remain in storage (no auto-clear on completion)
+	assert.Equal(t, 2, storage.Len())
+	requireMeta(t, result, 2)
 }
 
 func TestTodoTool_WithStorage(t *testing.T) {
@@ -282,6 +306,55 @@ func TestTodoTool_ParametersAreObjects(t *testing.T) {
 	}
 }
 
+func TestTodoTool_CreateTodo_FullStateOutput(t *testing.T) {
+	tool := NewTodoTool()
+
+	// Create first todo
+	result1, err := tool.handler.createTodo(t.Context(), CreateTodoArgs{Description: "First"})
+	require.NoError(t, err)
+	var out1 CreateTodoOutput
+	require.NoError(t, json.Unmarshal([]byte(result1.Output), &out1))
+	require.Len(t, out1.AllTodos, 1)
+	assert.Contains(t, out1.Reminder, "todo_1")
+
+	// Create second todo — response shows both
+	result2, err := tool.handler.createTodo(t.Context(), CreateTodoArgs{Description: "Second"})
+	require.NoError(t, err)
+	var out2 CreateTodoOutput
+	require.NoError(t, json.Unmarshal([]byte(result2.Output), &out2))
+	require.Len(t, out2.AllTodos, 2)
+	assert.Contains(t, out2.Reminder, "todo_1")
+	assert.Contains(t, out2.Reminder, "todo_2")
+}
+
+func TestTodoTool_UpdateTodos_FullStateOutput(t *testing.T) {
+	tool := NewTodoTool()
+
+	_, err := tool.handler.createTodos(t.Context(), CreateTodosArgs{
+		Descriptions: []string{"A", "B", "C"},
+	})
+	require.NoError(t, err)
+
+	result, err := tool.handler.updateTodos(t.Context(), UpdateTodosArgs{
+		Updates: []TodoUpdate{{ID: "todo_1", Status: "completed"}},
+	})
+	require.NoError(t, err)
+
+	var output UpdateTodosOutput
+	require.NoError(t, json.Unmarshal([]byte(result.Output), &output))
+
+	// AllTodos shows full state including the completed item
+	require.Len(t, output.AllTodos, 3)
+	assert.Equal(t, "completed", output.AllTodos[0].Status)
+	assert.Equal(t, "pending", output.AllTodos[1].Status)
+	assert.Equal(t, "pending", output.AllTodos[2].Status)
+
+	// Reminder only lists incomplete items
+	assert.NotContains(t, output.Reminder, "todo_1")
+	assert.Contains(t, output.Reminder, "todo_2")
+	assert.Contains(t, output.Reminder, "todo_3")
+}
+
 // requireMeta asserts that result.Meta is a []Todo of the expected length.
 func requireMeta(t *testing.T, result *tools.ToolCallResult, expectedLen int) {
 	t.Helper()