From 265e096a53a6952d99ac2109cff06ba3a672cb37 Mon Sep 17 00:00:00 2001
From: Chesars <cesarponce19544@gmail.com>
Date: Mon, 23 Mar 2026 11:06:52 -0300
Subject: [PATCH] fix: use correct parameter name 'dimension' for Vertex AI
 multimodalembedding

The Vertex AI multimodalembedding predict endpoint expects 'dimension'
(not 'outputDimensionality') in the parameters field.
---
 litellm/llms/vertex_ai/multimodal_embeddings/transformation.py  | 2 +-
 .../test_vertex_ai_multimodal_embedding_transformation.py       | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/litellm/llms/vertex_ai/multimodal_embeddings/transformation.py b/litellm/llms/vertex_ai/multimodal_embeddings/transformation.py
index d5cfca96812..f1d121099f9 100644
--- a/litellm/llms/vertex_ai/multimodal_embeddings/transformation.py
+++ b/litellm/llms/vertex_ai/multimodal_embeddings/transformation.py
@@ -203,7 +203,7 @@ class VertexAIMultimodalEmbeddingConfig(BaseEmbeddingConfig):
 
         if "outputDimensionality" in optional_params:
             request_data["parameters"] = {
-                "outputDimensionality": optional_params["outputDimensionality"]
+                "dimension": optional_params["outputDimensionality"]
             }
 
         return cast(dict, request_data)
diff --git a/tests/test_litellm/llms/vertex_ai/multimodal_embeddings/test_vertex_ai_multimodal_embedding_transformation.py b/tests/test_litellm/llms/vertex_ai/multimodal_embeddings/test_vertex_ai_multimodal_embedding_transformation.py
index e060e2a7e1a..19024104fe7 100644
--- a/tests/test_litellm/llms/vertex_ai/multimodal_embeddings/test_vertex_ai_multimodal_embedding_transformation.py
+++ b/tests/test_litellm/llms/vertex_ai/multimodal_embeddings/test_vertex_ai_multimodal_embedding_transformation.py
@@ -156,7 +156,7 @@ class TestVertexMultimodalEmbedding:
             headers={},
         )
         assert "parameters" in request, "Request should contain 'parameters' field"
-        assert request["parameters"]["outputDimensionality"] == 128
+        assert request["parameters"]["dimension"] == 128
 
     def test_no_parameters_field_when_dimensions_not_set(self):
         """Test that no parameters field is added when dimensions is not set."""