fix: Adding Embedding model to watsonx inference (#2118)

# What does this PR do?
Issue Link : https://github.com/meta-llama/llama-stack/issues/2117

## Test Plan
Once added, User will be able to use Sentence Transformer model
`all-MiniLM-L6-v2`

docs/source/distributions/remote_hosted_distro/watsonx.md

@@ -18,7 +18,7 @@ The `llamastack/distribution-watsonx` distribution consists of the following pro
 | agents | `inline::meta-reference` |
 | datasetio | `remote::huggingface`, `inline::localfs` |
 | eval | `inline::meta-reference` |
-| inference | `remote::watsonx` |
+| inference | `remote::watsonx`, `inline::sentence-transformers` |
 | safety | `inline::llama-guard` |
 | scoring | `inline::basic`, `inline::llm-as-judge`, `inline::braintrust` |
 | telemetry | `inline::meta-reference` |

llama_stack/templates/dependencies.json

@@ -833,6 +833,8 @@
     "tqdm",
     "transformers",
     "tree_sitter",
-    "uvicorn"
+    "uvicorn",
+    "sentence-transformers --no-deps",
+    "torch torchvision --index-url https://download.pytorch.org/whl/cpu"
   ]
 }

llama_stack/templates/watsonx/build.yaml

@@ -4,6 +4,7 @@ distribution_spec:
   providers:
     inference:
     - remote::watsonx
+    - inline::sentence-transformers
     vector_io:
     - inline::faiss
     safety:

llama_stack/templates/watsonx/run.yaml

@@ -18,6 +18,9 @@ providers:
       url: ${env.WATSONX_BASE_URL:https://us-south.ml.cloud.ibm.com}
       api_key: ${env.WATSONX_API_KEY:}
       project_id: ${env.WATSONX_PROJECT_ID:}
+  - provider_id: sentence-transformers
+    provider_type: inline::sentence-transformers
+    config: {}
   vector_io:
   - provider_id: faiss
     provider_type: inline::faiss
@@ -191,6 +194,11 @@ models:
   provider_id: watsonx
   provider_model_id: meta-llama/llama-guard-3-11b-vision
   model_type: llm
+- metadata:
+    embedding_dimension: 384
+  model_id: all-MiniLM-L6-v2
+  provider_id: sentence-transformers
+  model_type: embedding
 shields: []
 vector_dbs: []
 datasets: []

llama_stack/templates/watsonx/watsonx.py

@@ -6,7 +6,11 @@
 
 from pathlib import Path
 
-from llama_stack.distribution.datatypes import Provider, ToolGroupInput
+from llama_stack.apis.models.models import ModelType
+from llama_stack.distribution.datatypes import ModelInput, Provider, ToolGroupInput
+from llama_stack.providers.inline.inference.sentence_transformers import (
+    SentenceTransformersInferenceConfig,
+)
 from llama_stack.providers.remote.inference.watsonx import WatsonXConfig
 from llama_stack.providers.remote.inference.watsonx.models import MODEL_ENTRIES
 from llama_stack.templates.template import DistributionTemplate, RunConfigSettings, get_model_registry
@@ -14,7 +18,7 @@ from llama_stack.templates.template import DistributionTemplate, RunConfigSettin
 
 def get_distribution_template() -> DistributionTemplate:
     providers = {
-        "inference": ["remote::watsonx"],
+        "inference": ["remote::watsonx", "inline::sentence-transformers"],
         "vector_io": ["inline::faiss"],
         "safety": ["inline::llama-guard"],
         "agents": ["inline::meta-reference"],
@@ -36,6 +40,12 @@ def get_distribution_template() -> DistributionTemplate:
         config=WatsonXConfig.sample_run_config(),
     )
 
+    embedding_provider = Provider(
+        provider_id="sentence-transformers",
+        provider_type="inline::sentence-transformers",
+        config=SentenceTransformersInferenceConfig.sample_run_config(),
+    )
+
     available_models = {
         "watsonx": MODEL_ENTRIES,
     }
@@ -50,6 +60,15 @@ def get_distribution_template() -> DistributionTemplate:
         ),
     ]
 
+    embedding_model = ModelInput(
+        model_id="all-MiniLM-L6-v2",
+        provider_id="sentence-transformers",
+        model_type=ModelType.embedding,
+        metadata={
+            "embedding_dimension": 384,
+        },
+    )
+
     default_models = get_model_registry(available_models)
     return DistributionTemplate(
         name="watsonx",
@@ -62,9 +81,9 @@ def get_distribution_template() -> DistributionTemplate:
         run_configs={
             "run.yaml": RunConfigSettings(
                 provider_overrides={
-                    "inference": [inference_provider],
+                    "inference": [inference_provider, embedding_provider],
                 },
-                default_models=default_models,
+                default_models=default_models + [embedding_model],
                 default_tool_groups=default_tool_groups,
             ),
         },