refactor: default for max_new_tokens to 512 in Hugging Face generators

haystack/components/generators/chat/hugging_face_tgi.py

@@ -123,6 +123,7 @@ def __init__(
         check_generation_params(generation_kwargs, ["n"])
         generation_kwargs["stop_sequences"] = generation_kwargs.get("stop_sequences", [])
         generation_kwargs["stop_sequences"].extend(stop_words or [])
+        generation_kwargs.setdefault("max_new_tokens", 512)
 
         self.model = model
         self.url = url

haystack/components/generators/hugging_face_local.py

@@ -106,6 +106,7 @@ def __init__(
                 "Found both the `stop_words` init parameter and the `stopping_criteria` key in `generation_kwargs`. "
                 "Please specify only one of them."
             )
+        generation_kwargs.setdefault("max_new_tokens", 512)
 
         self.huggingface_pipeline_kwargs = huggingface_pipeline_kwargs
         self.generation_kwargs = generation_kwargs

haystack/components/generators/hugging_face_tgi.py

@@ -111,6 +111,7 @@ def __init__(
         check_generation_params(generation_kwargs, ["n"])
         generation_kwargs["stop_sequences"] = generation_kwargs.get("stop_sequences", [])
         generation_kwargs["stop_sequences"].extend(stop_words or [])
+        generation_kwargs.setdefault("max_new_tokens", 512)
 
         self.model = model
         self.url = url

releasenotes/notes/adjust-max-new-tokens-to-512-in-huggingface-generators-76d9aba116b65e70.yaml

@@ -0,0 +1,4 @@
+---
+enhancements:
+  - |
+    Set max_new_tokens default to 512 in Hugging Face generators.

test/components/generators/chat/test_hugging_face_tgi.py

@@ -1,14 +1,12 @@
-from unittest.mock import patch, MagicMock, Mock
-
-from haystack.utils.auth import Secret
+from unittest.mock import MagicMock, Mock, patch
 
 import pytest
-from huggingface_hub.inference._text_generation import TextGenerationStreamResponse, Token, StreamDetails, FinishReason
+from huggingface_hub.inference._text_generation import FinishReason, StreamDetails, TextGenerationStreamResponse, Token
 from huggingface_hub.utils import RepositoryNotFoundError
 
 from haystack.components.generators.chat import HuggingFaceTGIChatGenerator
-
-from haystack.dataclasses import StreamingChunk, ChatMessage
+from haystack.dataclasses import ChatMessage, StreamingChunk
+from haystack.utils.auth import Secret
 
 
 @pytest.fixture
@@ -70,7 +68,11 @@ def test_initialize_with_valid_model_and_generation_parameters(
         )
         generator.warm_up()
 
-        assert generator.generation_kwargs == {**generation_kwargs, **{"stop_sequences": ["stop"]}}
+        assert generator.generation_kwargs == {
+            **generation_kwargs,
+            **{"stop_sequences": ["stop"]},
+            **{"max_new_tokens": 512},
+        }
         assert generator.tokenizer is not None
         assert generator.client is not None
         assert generator.streaming_callback == streaming_callback
@@ -92,7 +94,7 @@ def test_to_dict(self, mock_check_valid_model):
         # Assert that the init_params dictionary contains the expected keys and values
         assert init_params["model"] == "NousResearch/Llama-2-7b-chat-hf"
         assert init_params["token"] == {"env_vars": ["ENV_VAR"], "strict": False, "type": "env_var"}
-        assert init_params["generation_kwargs"] == {"n": 5, "stop_sequences": ["stop", "words"]}
+        assert init_params["generation_kwargs"] == {"n": 5, "stop_sequences": ["stop", "words"], "max_new_tokens": 512}
 
     def test_from_dict(self, mock_check_valid_model):
         generator = HuggingFaceTGIChatGenerator(
@@ -106,7 +108,7 @@ def test_from_dict(self, mock_check_valid_model):
 
         generator_2 = HuggingFaceTGIChatGenerator.from_dict(result)
         assert generator_2.model == "NousResearch/Llama-2-7b-chat-hf"
-        assert generator_2.generation_kwargs == {"n": 5, "stop_sequences": ["stop", "words"]}
+        assert generator_2.generation_kwargs == {"n": 5, "stop_sequences": ["stop", "words"], "max_new_tokens": 512}
         assert generator_2.streaming_callback is streaming_callback_handler
 
     def test_warm_up(self, mock_check_valid_model, mock_auto_tokenizer, mock_list_inference_deployed_models):
@@ -205,7 +207,7 @@ def test_generate_text_response_with_valid_prompt_and_generation_parameters(
         # check kwargs passed to text_generation
         # note how n because it is not text generation parameter was not passed to text_generation
         _, kwargs = mock_text_generation.call_args
-        assert kwargs == {"details": True, "stop_sequences": ["stop"]}
+        assert kwargs == {"details": True, "stop_sequences": ["stop"], "max_new_tokens": 512}
 
         assert isinstance(response, dict)
         assert "replies" in response
@@ -240,7 +242,7 @@ def test_generate_multiple_text_responses_with_valid_prompt_and_generation_param
 
         # check kwargs passed to text_generation
         _, kwargs = mock_text_generation.call_args
-        assert kwargs == {"details": True, "stop_sequences": ["stop"]}
+        assert kwargs == {"details": True, "stop_sequences": ["stop"], "max_new_tokens": 512}
 
         # note how n caused n replies to be generated
         assert isinstance(response, dict)
@@ -268,7 +270,7 @@ def test_generate_text_with_stop_words(
         # check kwargs passed to text_generation
         # we translate stop_words to stop_sequences
         _, kwargs = mock_text_generation.call_args
-        assert kwargs == {"details": True, "stop_sequences": ["stop", "words"]}
+        assert kwargs == {"details": True, "stop_sequences": ["stop", "words"], "max_new_tokens": 512}
 
         # Assert that the response contains the generated replies
         assert "replies" in response
@@ -343,7 +345,7 @@ def mock_iter(self):
 
         # check kwargs passed to text_generation
         _, kwargs = mock_text_generation.call_args
-        assert kwargs == {"details": True, "stop_sequences": [], "stream": True}
+        assert kwargs == {"details": True, "stop_sequences": [], "stream": True, "max_new_tokens": 512}
 
         # Assert that the streaming callback was called twice
         assert streaming_call_count == 2

test/components/generators/test_hugging_face_local_generator.py

@@ -4,10 +4,10 @@
 import pytest
 import torch
 from transformers import PreTrainedTokenizerFast
-from haystack.utils.auth import Secret
 
 from haystack.components.generators.hugging_face_local import HuggingFaceLocalGenerator, StopWordsCriteria
 from haystack.utils import ComponentDevice
+from haystack.utils.auth import Secret
 
 
 class TestHuggingFaceLocalGenerator:
@@ -23,7 +23,7 @@ def test_init_default(self, model_info_mock, monkeypatch):
             "token": None,
             "device": ComponentDevice.resolve_device(None).to_hf(),
         }
-        assert generator.generation_kwargs == {}
+        assert generator.generation_kwargs == {"max_new_tokens": 512}
         assert generator.pipeline is None
 
     def test_init_custom_token(self):
@@ -124,7 +124,7 @@ def test_init_set_return_full_text(self):
         """
         generator = HuggingFaceLocalGenerator(task="text-generation")
 
-        assert generator.generation_kwargs == {"return_full_text": False}
+        assert generator.generation_kwargs == {"max_new_tokens": 512, "return_full_text": False}
 
     def test_init_fails_with_both_stopwords_and_stoppingcriteria(self):
         with pytest.raises(
@@ -153,7 +153,7 @@ def test_to_dict_default(self, model_info_mock):
                     "task": "text2text-generation",
                     "device": ComponentDevice.resolve_device(None).to_hf(),
                 },
-                "generation_kwargs": {},
+                "generation_kwargs": {"max_new_tokens": 512},
                 "stop_words": None,
             },
         }

test/components/generators/test_hugging_face_tgi.py

@@ -1,7 +1,7 @@
-from unittest.mock import patch, MagicMock, Mock
+from unittest.mock import MagicMock, Mock, patch
 
 import pytest
-from huggingface_hub.inference._text_generation import TextGenerationStreamResponse, Token, StreamDetails, FinishReason
+from huggingface_hub.inference._text_generation import FinishReason, StreamDetails, TextGenerationStreamResponse, Token
 from huggingface_hub.utils import RepositoryNotFoundError
 
 from haystack.components.generators import HuggingFaceTGIGenerator
@@ -63,7 +63,11 @@ def test_initialize_with_valid_model_and_generation_parameters(self, mock_check_
         )
 
         assert generator.model == model
-        assert generator.generation_kwargs == {**generation_kwargs, **{"stop_sequences": ["stop"]}}
+        assert generator.generation_kwargs == {
+            **generation_kwargs,
+            **{"stop_sequences": ["stop"]},
+            **{"max_new_tokens": 512},
+        }
         assert generator.tokenizer is None
         assert generator.client is not None
         assert generator.streaming_callback == streaming_callback
@@ -84,7 +88,7 @@ def test_to_dict(self, mock_check_valid_model):
         # Assert that the init_params dictionary contains the expected keys and values
         assert init_params["model"] == "mistralai/Mistral-7B-v0.1"
         assert init_params["token"] == {"env_vars": ["ENV_VAR"], "strict": False, "type": "env_var"}
-        assert init_params["generation_kwargs"] == {"n": 5, "stop_sequences": ["stop", "words"]}
+        assert init_params["generation_kwargs"] == {"n": 5, "stop_sequences": ["stop", "words"], "max_new_tokens": 512}
 
     def test_from_dict(self, mock_check_valid_model):
         generator = HuggingFaceTGIGenerator(
@@ -99,7 +103,7 @@ def test_from_dict(self, mock_check_valid_model):
         # now deserialize, call from_dict
         generator_2 = HuggingFaceTGIGenerator.from_dict(result)
         assert generator_2.model == "mistralai/Mistral-7B-v0.1"
-        assert generator_2.generation_kwargs == {"n": 5, "stop_sequences": ["stop", "words"]}
+        assert generator_2.generation_kwargs == {"n": 5, "stop_sequences": ["stop", "words"], "max_new_tokens": 512}
         assert generator_2.streaming_callback is streaming_callback_handler
 
     def test_initialize_with_invalid_url(self, mock_check_valid_model):
@@ -135,7 +139,7 @@ def test_generate_text_response_with_valid_prompt_and_generation_parameters(
         # check kwargs passed to text_generation
         # note how n was not passed to text_generation
         _, kwargs = mock_text_generation.call_args
-        assert kwargs == {"details": True, "stop_sequences": ["stop"]}
+        assert kwargs == {"details": True, "stop_sequences": ["stop"], "max_new_tokens": 512}
 
         assert isinstance(response, dict)
         assert "replies" in response
@@ -168,7 +172,7 @@ def test_generate_multiple_text_responses_with_valid_prompt_and_generation_param
         # check kwargs passed to text_generation
         # note how n was not passed to text_generation
         _, kwargs = mock_text_generation.call_args
-        assert kwargs == {"details": True, "stop_sequences": ["stop"]}
+        assert kwargs == {"details": True, "stop_sequences": ["stop"], "max_new_tokens": 512}
 
         assert isinstance(response, dict)
         assert "replies" in response
@@ -208,7 +212,7 @@ def test_generate_text_with_stop_words(
 
         # check kwargs passed to text_generation
         _, kwargs = mock_text_generation.call_args
-        assert kwargs == {"details": True, "stop_sequences": ["stop", "words"]}
+        assert kwargs == {"details": True, "stop_sequences": ["stop", "words"], "max_new_tokens": 512}
 
         # Assert that the response contains the generated replies
         assert "replies" in response
@@ -283,7 +287,7 @@ def mock_iter(self):
 
         # check kwargs passed to text_generation
         _, kwargs = mock_text_generation.call_args
-        assert kwargs == {"details": True, "stop_sequences": [], "stream": True}
+        assert kwargs == {"details": True, "stop_sequences": [], "stream": True, "max_new_tokens": 512}
 
         # Assert that the streaming callback was called twice
         assert streaming_call_count == 2