diff --git a/lib/cli/src/crewai_cli/deploy/validate.py b/lib/cli/src/crewai_cli/deploy/validate.py
index e75c813ec..0b2564d24 100644
--- a/lib/cli/src/crewai_cli/deploy/validate.py
+++ b/lib/cli/src/crewai_cli/deploy/validate.py
@@ -172,9 +172,7 @@ class DeployValidator:
         except Exception:
             return False
         crewai_config = get_crewai_project_config(data)
-        return crewai_config.get("type") == "crew" and bool(
-            crewai_config.get("definition", "").strip()
-        )
+        return crewai_config.get("type") == "crew" and "definition" in crewai_config
 
     def run(self) -> list[ValidationResult]:
         """Run all checks. Later checks are skipped when earlier ones make
diff --git a/lib/cli/tests/deploy/test_validate.py b/lib/cli/tests/deploy/test_validate.py
index fec541dbb..31ecb0c8b 100644
--- a/lib/cli/tests/deploy/test_validate.py
+++ b/lib/cli/tests/deploy/test_validate.py
@@ -569,6 +569,22 @@ def test_is_json_crew_false_for_declared_crew_without_definition(tmp_path):
     assert DeployValidator(project_root=tmp_path)._is_json_crew is False
 
 
+def test_json_crew_non_string_definition_reports_invalid_definition(
+    tmp_path: Path,
+) -> None:
+    (tmp_path / "pyproject.toml").write_text(
+        '[project]\nname = "demo"\nversion = "0.1.0"\n\n'
+        '[tool.crewai]\ntype = "crew"\ndefinition = ["crew.jsonc"]\n'
+    )
+
+    v = DeployValidator(project_root=tmp_path)
+    v.run()
+
+    finding = next(r for r in v.results if r.code == "invalid_crew_definition")
+    assert finding.severity is Severity.ERROR
+    assert "must be a string" in finding.detail
+
+
 def test_is_json_crew_false_without_pyproject(tmp_path):
     (tmp_path / "crew.jsonc").write_text("{}")
 
diff --git a/lib/crewai-core/src/crewai_core/project.py b/lib/crewai-core/src/crewai_core/project.py
index 18fc68a77..9c7e6a33e 100644
--- a/lib/crewai-core/src/crewai_core/project.py
+++ b/lib/crewai-core/src/crewai_core/project.py
@@ -71,9 +71,20 @@ def configured_project_definition(
     if crewai_config.get("type") != project_type:
         return None
 
-    definition = crewai_config.get("definition", "").strip()
-    if not definition:
+    if "definition" not in crewai_config:
         return None
+    raw_definition = crewai_config["definition"]
+    if not isinstance(raw_definition, str):
+        raise ProjectDefinitionError(
+            "[tool.crewai] definition must be a string project-local path; "
+            f"got {raw_definition!r}."
+        )
+
+    definition = raw_definition.strip()
+    if not definition:
+        raise ProjectDefinitionError(
+            "[tool.crewai] definition must be a non-empty project-local path."
+        )
 
     return resolve_project_definition_path(definition=definition, project_root=root)
 
diff --git a/lib/crewai-core/tests/test_smoke.py b/lib/crewai-core/tests/test_smoke.py
index 76414d835..3decdaa73 100644
--- a/lib/crewai-core/tests/test_smoke.py
+++ b/lib/crewai-core/tests/test_smoke.py
@@ -139,6 +139,42 @@ def test_configured_project_definition_rejects_project_escape(tmp_path: Path) ->
         )
 
 
+def test_configured_project_definition_rejects_non_string_definition(
+    tmp_path: Path,
+) -> None:
+    with pytest.raises(project.ProjectDefinitionError, match="must be a string"):
+        project.configured_project_definition(
+            "crew",
+            pyproject_data={
+                "tool": {
+                    "crewai": {
+                        "type": "crew",
+                        "definition": ["crew.jsonc"],
+                    }
+                }
+            },
+            project_root=tmp_path,
+        )
+
+
+def test_configured_project_definition_rejects_empty_definition(
+    tmp_path: Path,
+) -> None:
+    with pytest.raises(project.ProjectDefinitionError, match="non-empty"):
+        project.configured_project_definition(
+            "crew",
+            pyproject_data={
+                "tool": {
+                    "crewai": {
+                        "type": "crew",
+                        "definition": "  ",
+                    }
+                }
+            },
+            project_root=tmp_path,
+        )
+
+
 def test_core_telemetry_skips_duplicate_tracer_provider(
     monkeypatch: pytest.MonkeyPatch,
 ) -> None:
diff --git a/lib/crewai/src/crewai/utilities/reset_memories.py b/lib/crewai/src/crewai/utilities/reset_memories.py
index 83ad0747c..2470454dc 100644
--- a/lib/crewai/src/crewai/utilities/reset_memories.py
+++ b/lib/crewai/src/crewai/utilities/reset_memories.py
@@ -137,3 +137,4 @@ def reset_memories_command(
 
     except Exception as e:
         click.echo(f"An unexpected error occurred: {e}", err=True)
+        raise SystemExit(1) from e
diff --git a/lib/crewai/tests/cli/test_cli.py b/lib/crewai/tests/cli/test_cli.py
index b4e23cc95..387e3bb3d 100644
--- a/lib/crewai/tests/cli/test_cli.py
+++ b/lib/crewai/tests/cli/test_cli.py
@@ -280,6 +280,7 @@ def test_reset_invalid_json_crew_blocks_reset(
 
     mock_load_crew.assert_called_once_with((tmp_path / "crew.jsonc").resolve())
     mock_crew.reset_memories.assert_not_called()
+    assert result.exit_code != 0
     assert "An unexpected error occurred: invalid JSON" in result.output