diff --git a/src/specify_cli/bundler/models/manifest.py b/src/specify_cli/bundler/models/manifest.py
index 4a903fbd18..e7969683c9 100644
--- a/src/specify_cli/bundler/models/manifest.py
+++ b/src/specify_cli/bundler/models/manifest.py
@@ -122,6 +122,11 @@ def from_dict(cls, data: Any) -> "BundleManifest":
 
         integration = None
         integration_raw = data.get("integration")
+        # Mirror the requires/provides guards above: a present-but-non-mapping
+        # 'integration' (e.g. a bare string "copilot") was silently dropped,
+        # leaving the bundle wrongly integration-agnostic. Reject it instead.
+        if integration_raw is not None and not isinstance(integration_raw, dict):
+            raise BundlerError("'integration' must be a mapping when present.")
         if isinstance(integration_raw, dict) and integration_raw.get("id"):
             integration = IntegrationRef(id=str(integration_raw["id"]).strip())
 
diff --git a/tests/contract/test_manifest_schema.py b/tests/contract/test_manifest_schema.py
index 4d0d95f608..1c1c279868 100644
--- a/tests/contract/test_manifest_schema.py
+++ b/tests/contract/test_manifest_schema.py
@@ -124,3 +124,13 @@ def test_string_mcp_rejected_not_split_per_character():
     data["requires"]["mcp"] = "github"
     with pytest.raises(BundlerError, match="'requires.mcp' must be a list of strings"):
         BundleManifest.from_dict(data)
+
+
+def test_string_integration_rejected_not_silently_dropped():
+    # A present-but-non-mapping 'integration' (a bare string) was silently
+    # dropped, leaving the bundle wrongly integration-agnostic. Reject it like
+    # the sibling requires/provides mapping fields.
+    data = valid_manifest_dict()
+    data["integration"] = "copilot"
+    with pytest.raises(BundlerError, match="'integration' must be a mapping when present"):
+        BundleManifest.from_dict(data)