feat: Add Jina Embeddings v3 with task-specific LoRA support

Add support for jinaai/jina-embeddings-v3, a multilingual embedding model
with 1024 dimensions supporting 89+ languages and task-specific LoRA adapters.

Features:
- Task-specific embeddings via LoRA adapters (retrieval.query, retrieval.passage,
  classification, text-matching, separation)
- Automatic task_id handling for ONNX inference
- Default to text-matching task for general purpose use
- query_embed() and passage_embed() methods for retrieval tasks
- Matryoshka dimensions support (32-1024)
- 8,192 token context window

Model specs:
- 570M parameters
- 2.29 GB ONNX model
- Apache 2.0 license

Implementation:
- Added model configuration with additional_files for model.onnx_data
- Load lora_adaptations from config.json
- Preprocess ONNX input to add task_id parameter
- Override query_embed/passage_embed for automatic task selection
- Added comprehensive multi-task test with canonical vectors

Following the pattern from PR qdrant#561 but using task_id instead of text prefixes.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

Author: aaronspring

fastembed/text/onnx_embedding.py

@@ -1,5 +1,9 @@
+import json
+from pathlib import Path
 from typing import Any, Iterable, Optional, Sequence, Type, Union
 
+import numpy as np
+
 from fastembed.common.types import NumpyArray, OnnxProvider
 from fastembed.common.onnx_model import OnnxOutputContext
 from fastembed.common.utils import define_cache_dir, normalize
@@ -180,6 +184,24 @@
         sources=ModelSource(hf="jinaai/jina-clip-v1"),
         model_file="onnx/text_model.onnx",
     ),
+    DenseModelDescription(
+        model="jinaai/jina-embeddings-v3",
+        dim=1024,
+        description=(
+            "Text embeddings, Unimodal (text), Multilingual (89+ languages), 8192 input tokens truncation, "
+            "Task-specific LoRA adapters (retrieval, classification, text-matching, clustering), "
+            "Matryoshka dimensions: 32-1024, 2024 year."
+        ),
+        license="apache-2.0",
+        size_in_GB=2.29,
+        sources=ModelSource(hf="jinaai/jina-embeddings-v3"),
+        model_file="onnx/model.onnx",
+        additional_files=["onnx/model.onnx_data"],
+        tasks={
+            "query_task": "retrieval.query",
+            "passage_task": "retrieval.passage",
+        },
+    ),
 ]
 
 
@@ -255,6 +277,14 @@ def __init__(
             specific_model_path=self._specific_model_path,
         )
 
+        # Load LoRA adaptations for models that support task-specific embeddings (e.g., Jina v3)
+        self.lora_adaptations: Optional[list[str]] = None
+        config_path = Path(self._model_dir) / "config.json"
+        if config_path.exists():
+            with open(config_path, "r") as f:
+                config = json.load(f)
+                self.lora_adaptations = config.get("lora_adaptations")
+
         if not self.lazy_load:
             self.load_onnx_model()
 
@@ -303,7 +333,20 @@ def _preprocess_onnx_input(
     ) -> dict[str, NumpyArray]:
         """
         Preprocess the onnx input.
+        Adds task_id for models with LoRA adapters (e.g., Jina v3).
         """
+        # Handle task-specific embeddings for models with LoRA adapters
+        if self.lora_adaptations:
+            task_type = kwargs.get("task_type")
+
+            # If no task specified, use default (text-matching for general purpose)
+            if not task_type:
+                # Default to text-matching if available, otherwise first task
+                task_type = "text-matching" if "text-matching" in self.lora_adaptations else self.lora_adaptations[0]
+
+            if task_type in self.lora_adaptations:
+                task_id = np.array(self.lora_adaptations.index(task_type), dtype=np.int64)
+                onnx_input["task_id"] = task_id
         return onnx_input
 
     def _post_process_onnx_output(
@@ -329,6 +372,46 @@ def load_onnx_model(self) -> None:
             device_id=self.device_id,
         )
 
+    def query_embed(self, query: Union[str, Iterable[str]], **kwargs: Any) -> Iterable[NumpyArray]:
+        """
+        Embeds queries with task-specific handling for models that support it.
+
+        Args:
+            query (Union[str, Iterable[str]]): The query to embed, or an iterable e.g. list of queries.
+            **kwargs: Additional keyword arguments.
+
+        Returns:
+            Iterable[NumpyArray]: The embeddings.
+        """
+        # Use task-specific embedding for models with LoRA adapters
+        if self.model_description.tasks and "query_task" in self.model_description.tasks:
+            kwargs["task_type"] = self.model_description.tasks["query_task"]
+
+        if isinstance(query, str):
+            yield from self.embed([query], **kwargs)
+        else:
+            yield from self.embed(query, **kwargs)
+
+    def passage_embed(self, texts: Union[str, Iterable[str]], **kwargs: Any) -> Iterable[NumpyArray]:
+        """
+        Embeds passages with task-specific handling for models that support it.
+
+        Args:
+            texts (Union[str, Iterable[str]]): The text(s) to embed.
+            **kwargs: Additional keyword arguments.
+
+        Returns:
+            Iterable[NumpyArray]: The embeddings.
+        """
+        # Use task-specific embedding for models with LoRA adapters
+        if self.model_description.tasks and "passage_task" in self.model_description.tasks:
+            kwargs["task_type"] = self.model_description.tasks["passage_task"]
+
+        if isinstance(texts, str):
+            yield from self.embed([texts], **kwargs)
+        else:
+            yield from self.embed(texts, **kwargs)
+
 
 class OnnxTextEmbeddingWorker(TextEmbeddingWorker[NumpyArray]):
     def init_embedding(

tests/test_text_onnx_embeddings.py

@@ -67,6 +67,7 @@
     "Qdrant/clip-ViT-B-32-text": np.array([0.0083, 0.0103, -0.0138, 0.0199, -0.0069]),
     "thenlper/gte-base": np.array([0.0038, 0.0355, 0.0181, 0.0092, 0.0654]),
     "jinaai/jina-clip-v1": np.array([-0.0862, -0.0101, -0.0056, 0.0375, -0.0472]),
+    "jinaai/jina-embeddings-v3": np.array([0.07257809, -0.08073004, 0.09241360, -0.01755937, 0.06534681]),
 }
 
 MULTI_TASK_MODELS = ["jinaai/jina-embeddings-v3"]
@@ -175,3 +176,64 @@ def test_embedding_size() -> None:
 
     if is_ci:
         delete_model_cache(model.model._model_dir)
+
+
+@pytest.mark.parametrize("model_name", MULTI_TASK_MODELS)
+def test_multi_task_embedding(model_name: str) -> None:
+    """Test models that support task-specific embeddings (query vs passage)."""
+    is_ci = os.getenv("CI")
+    is_manual = os.getenv("GITHUB_EVENT_NAME") == "workflow_dispatch"
+
+    # Skip in CI unless manual
+    if is_ci and not is_manual:
+        pytest.skip("Skipping multi-task model tests in CI (large models)")
+
+    model_desc = None
+    for desc in TextEmbedding._list_supported_models():
+        if desc.model == model_name:
+            model_desc = desc
+            break
+
+    assert model_desc is not None, f"Model {model_name} not found in supported models"
+
+    dim = model_desc.dim
+    model = TextEmbedding(model_name=model_name)
+
+    # Test query embedding
+    queries = ["What is the capital of France?", "How does photosynthesis work?"]
+    query_embeddings = list(model.query_embed(queries))
+    query_embeddings = np.stack(query_embeddings, axis=0)
+    assert query_embeddings.shape == (2, dim), f"Query embeddings shape mismatch for {model_name}"
+
+    # Test passage embedding
+    passages = ["Paris is the capital of France.", "Photosynthesis is a process used by plants."]
+    passage_embeddings = list(model.passage_embed(passages))
+    passage_embeddings = np.stack(passage_embeddings, axis=0)
+    assert passage_embeddings.shape == (2, dim), f"Passage embeddings shape mismatch for {model_name}"
+
+    # Test regular embed (should work without task specification)
+    docs = ["hello world", "flag embedding"]
+    embeddings = list(model.embed(docs))
+    embeddings = np.stack(embeddings, axis=0)
+    assert embeddings.shape == (2, dim), f"Regular embeddings shape mismatch for {model_name}"
+
+    # Verify that query and passage embeddings are different (due to different LoRA adapters)
+    # Using the same text should produce different embeddings for query vs passage
+    test_text = "This is a test sentence"
+    query_emb = np.array(list(model.query_embed([test_text])))
+    passage_emb = np.array(list(model.passage_embed([test_text])))
+
+    # They should not be identical (different task adapters)
+    assert not np.allclose(query_emb, passage_emb, atol=1e-6), \
+        f"Query and passage embeddings should differ for {model_name}"
+
+    # Optional: Check canonical vectors if available
+    if model_name in CANONICAL_VECTOR_VALUES:
+        canonical_vector = CANONICAL_VECTOR_VALUES[model_name]
+        # Check against regular embeddings[0] which is "hello world"
+        assert np.allclose(
+            embeddings[0, : canonical_vector.shape[0]], canonical_vector, atol=1e-3
+        ), f"Canonical vector mismatch for {model_name}"
+
+    if is_ci:
+        delete_model_cache(model.model._model_dir)