fix(embedding): respect drop_params for unsupported dimensions parameter

The OpenAI-provider branch in `get_optional_params_embeddings` hard-raised
`UnsupportedParamsError` whenever `dimensions` was passed to a non
`text-embedding-3` model, even though the error message itself instructed
users to set `litellm.drop_params=True`. The flag (per-call and global)
was never consulted on this path, breaking the documented escape hatch
for users proxying to vLLM/TEI/Ollama-compat embedding servers via the
`openai/...` model prefix.

Now mirror the `drop_params` handling already used by `_check_valid_arg`
in the same function: when either `drop_params=True` (per-call) or
`litellm.drop_params=True` (global) is set, silently strip `dimensions`
from `non_default_params` and continue; otherwise preserve the existing
error to keep current behavior for users who have not opted in.

Adds two regression tests (per-call and global flag) and pins the
existing raise-by-default behavior against accidental future drift.

Fixes #26787

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

litellm/utils.py

@@ -3309,12 +3309,19 @@ def get_optional_params_embeddings(  # noqa: PLR0915
             and "dimensions" in non_default_params.keys()
             and "dimensions" not in (allowed_openai_params or [])
         ):
-            raise UnsupportedParamsError(
-                status_code=500,
-                message="Setting dimensions is not supported for OpenAI `text-embedding-3` and later models. To drop it from the call, set `litellm.drop_params = True`.",
-            )
-        else:
-            optional_params = non_default_params
+            # Honor drop_params (per-call) and litellm.drop_params (global) the same
+            # way `_check_valid_arg` does above. The raised error message itself
+            # tells users to set `drop_params=True`, so respect it here.
+            if litellm.drop_params is True or (
+                drop_params is not None and drop_params is True
+            ):
+                non_default_params.pop("dimensions", None)
+            else:
+                raise UnsupportedParamsError(
+                    status_code=500,
+                    message="Setting dimensions is not supported for OpenAI `text-embedding-3` and later models. To drop it from the call, set `litellm.drop_params = True`.",
+                )
+        optional_params = non_default_params
     elif custom_llm_provider == "triton":
         supported_params = get_supported_openai_params(
             model=model,

tests/local_testing/test_get_optional_params_embeddings.py

@@ -97,12 +97,69 @@ def test_openai_non_text_embedding_3_without_allowed_openai_params_raises():
     """
     from litellm.exceptions import UnsupportedParamsError
 
-    model, custom_llm_provider, _, _ = get_llm_provider(
-        model="openai/nvidia/llama-3.2-nv-embedqa-1b-v2"
-    )
-    with pytest.raises(UnsupportedParamsError):
-        get_optional_params_embeddings(
+    # ensure global drop_params is off (other tests in this file flip it on)
+    prev_drop_params = litellm.drop_params
+    litellm.drop_params = False
+    try:
+        model, custom_llm_provider, _, _ = get_llm_provider(
+            model="openai/nvidia/llama-3.2-nv-embedqa-1b-v2"
+        )
+        with pytest.raises(UnsupportedParamsError):
+            get_optional_params_embeddings(
+                model=model,
+                dimensions=1024,
+                custom_llm_provider=custom_llm_provider,
+            )
+    finally:
+        litellm.drop_params = prev_drop_params
+
+
+def test_openai_non_text_embedding_3_drop_params_per_call():
+    """
+    Regression for https://github.com/BerriAI/litellm/issues/26787
+
+    When drop_params=True is passed per-call, `dimensions` should be silently
+    stripped for a non-`text-embedding-3` OpenAI-provider model instead of
+    raising UnsupportedParamsError.
+    """
+    prev_drop_params = litellm.drop_params
+    litellm.drop_params = False  # ensure only per-call flag is in effect
+    try:
+        model, custom_llm_provider, _, _ = get_llm_provider(
+            model="openai/Qwen/Qwen3-Embedding-0.6B"
+        )
+        optional_params = get_optional_params_embeddings(
+            model=model,
+            dimensions=1024,
+            custom_llm_provider=custom_llm_provider,
+            drop_params=True,
+        )
+        print(f"received optional_params: {optional_params}")
+        assert "dimensions" not in optional_params
+    finally:
+        litellm.drop_params = prev_drop_params
+
+
+def test_openai_non_text_embedding_3_drop_params_global():
+    """
+    Regression for https://github.com/BerriAI/litellm/issues/26787
+
+    When `litellm.drop_params = True` is set globally, `dimensions` should be
+    silently stripped for a non-`text-embedding-3` OpenAI-provider model
+    instead of raising UnsupportedParamsError.
+    """
+    prev_drop_params = litellm.drop_params
+    litellm.drop_params = True
+    try:
+        model, custom_llm_provider, _, _ = get_llm_provider(
+            model="openai/Qwen/Qwen3-Embedding-0.6B"
+        )
+        optional_params = get_optional_params_embeddings(
             model=model,
             dimensions=1024,
             custom_llm_provider=custom_llm_provider,
         )
+        print(f"received optional_params: {optional_params}")
+        assert "dimensions" not in optional_params
+    finally:
+        litellm.drop_params = prev_drop_params