17ac44c · Agent Time Ledger

Add mark_list MCP tool

The MCP server could start and check individual marks by name but had no
way to enumerate existing marks. Agents that cannot recall a mark name
have no recovery path short of guessing.

Wire service.ListMarks into the MCP handler as the mark_list tool and
add tests covering the empty case, listing multiple marks, and verifying
deleted marks are excluded.

17ac44c Zion Boggan committed on Jun 29, 2026 (1 month ago)

README.md +1 -0

		@@ -81,6 +81,7 @@ JSON responses include a `confidence` value. For v0.1, persisted elapsed calcula
		- `session_status`
		- `mark_start`
		- `mark_elapsed`
	+	- `mark_list`
		- `stale_check`
		- `ledger_event`
		- `ledger_report`

internal/ledger/ledger_test.go +60 -0

		@@ -123,6 +123,66 @@ func TestStatePersistence(t *testing.T) {
		}
		}

	+	func TestListMarksEmpty(t *testing.T) {
	+	service := testService(t, time.Date(2026, 6, 19, 6, 30, 0, 0, time.UTC))
	+	marks, err := service.ListMarks()
	+	if err != nil {
	+	t.Fatalf("ListMarks returned error: %v", err)
	+	}
	+	if len(marks) != 0 {
	+	t.Fatalf("expected 0 marks, got %d", len(marks))
	+	}
	+	}
	+
	+	func TestListMarksReturnsAll(t *testing.T) {
	+	now := time.Date(2026, 6, 19, 6, 30, 0, 0, time.UTC)
	+	service := testService(t, now)
	+	if _, err := service.StartMark("build"); err != nil {
	+	t.Fatalf("StartMark(build) returned error: %v", err)
	+	}
	+	if _, err := service.StartMark("test"); err != nil {
	+	t.Fatalf("StartMark(test) returned error: %v", err)
	+	}
	+	marks, err := service.ListMarks()
	+	if err != nil {
	+	t.Fatalf("ListMarks returned error: %v", err)
	+	}
	+	if len(marks) != 2 {
	+	t.Fatalf("expected 2 marks, got %d", len(marks))
	+	}
	+	names := map[string]struct{}{}
	+	for _, m := range marks {
	+	names[m.Name] = struct{}{}
	+	}
	+	if _, ok := names["build"]; !ok {
	+	t.Fatal("mark 'build' not in ListMarks result")
	+	}
	+	if _, ok := names["test"]; !ok {
	+	t.Fatal("mark 'test' not in ListMarks result")
	+	}
	+	}
	+
	+	func TestListMarksExcludesDeleted(t *testing.T) {
	+	now := time.Date(2026, 6, 19, 6, 30, 0, 0, time.UTC)
	+	service := testService(t, now)
	+	if _, err := service.StartMark("build"); err != nil {
	+	t.Fatalf("StartMark returned error: %v", err)
	+	}
	+	if _, err := service.StartMark("deploy"); err != nil {
	+	t.Fatalf("StartMark returned error: %v", err)
	+	}
	+	if err := service.DeleteMark("deploy"); err != nil {
	+	t.Fatalf("DeleteMark returned error: %v", err)
	+	}
	+	marks, err := service.ListMarks()
	+	if err != nil {
	+	t.Fatalf("ListMarks returned error: %v", err)
	+	}
	+	if len(marks) != 1 \|\| marks[0].Name != "build" {
	+	t.Fatalf("expected [build], got %v", marks)
	+	}
	+	}
	+
		func TestJSONLEventValidity(t *testing.T) {
		dir := t.TempDir()
		service := NewService(state.NewStore(dir))

internal/mcp/mcp.go +3 -0

		@@ -158,6 +158,8 @@ func handleToolCall(raw json.RawMessage, service *ledger.Service) (callResult, e
		result, err = service.MarkElapsed(requiredString(args, "name"))
		case "stale_check":
		result, err = staleCheck(args, service)
	+	case "mark_list":
	+	result, err = service.ListMarks()
		case "ledger_event":
		note, _ := args["note"].(string)
		err = service.LedgerEvent(note)
		@@ -211,6 +213,7 @@ func tools() []map[string]any {
		tool("mark_elapsed", "Return elapsed time for a named mark.", map[string]any{
		"name": stringSchema("Mark name"),
		}, "name"),
	+	tool("mark_list", "Return all open marks with elapsed time.", map[string]any{}),
		tool("stale_check", "Check whether a timestamp or mark is stale for a TTL.", map[string]any{
		"timestamp": stringSchema("RFC3339 timestamp"),
		"mark": stringSchema("Existing mark name"),