Break computation if retriever doesn't find relevant docs and return standard response

[fabioballabiolm]

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Example Code

# Standard langchain RAG pipe

retriever = # whatever_retriever
llm = # whatever_llm
history_aware_retriever = create_history_aware_retriever(
        llm,
        retriever,
        question_contextualization_prompt,
)
question_answer_chain = create_stuff_documents_chain(
      llm, qa_prompt
)
rag_chain = create_retrieval_chain(history_aware_retriever, question_answer_chain)

Description

Let's say i built a RAG pipeline using langchain.

• Is there a way to break computation during retireval, if no relevant documentation is found (given a similarity threshold"), and return a standard response instead of still going into LLM for generation with empty context?
• Is there a way to break computation during retireval, if no relevant documentation is found (given a similarity threshold"), and go into LLM with a different prompt which for instant doesn't say to rely on context so that LLM can leverage it full "knowledge"?

Thanks in advance

System Info

aiohttp==3.9.5
aiosignal==1.3.1
altair==5.3.0
antlr4-python3-runtime==4.9.3
anyio==4.3.0
asttokens==2.4.1
async-timeout==4.0.3
attrs==23.2.0
backoff==2.2.1
beautifulsoup4==4.12.3
black==24.4.2
blinker==1.8.2
cachetools==5.3.3
certifi==2024.2.2
cffi==1.16.0
chardet==5.2.0
charset-normalizer==3.3.2
click==8.1.7
colorama==0.4.6
coloredlogs==15.0.1
comm==0.2.2
contourpy==1.2.1
cryptography==42.0.7
cycler==0.12.1
dataclasses-json==0.6.6
debugpy==1.8.2
decorator==5.1.1
deepdiff==7.0.1
Deprecated==1.2.14
distro==1.9.0
docstring_parser==0.16
effdet==0.4.1
emoji==2.12.1
exceptiongroup==1.2.1
executing==2.0.1
fastapi==0.110.3
filelock==3.14.0
filetype==1.2.0
flatbuffers==24.3.25
fonttools==4.51.0
frozenlist==1.4.1
fsspec==2024.5.0
gitdb==4.0.11
GitPython==3.1.43
google-api-core==2.19.0
google-api-python-client==2.129.0
google-auth==2.29.0
google-auth-httplib2==0.2.0
google-auth-oauthlib==1.2.0
google-cloud-aiplatform==1.52.0
google-cloud-bigquery==3.23.1
google-cloud-core==2.4.1
google-cloud-firestore==2.16.0
google-cloud-resource-manager==1.12.3
google-cloud-secret-manager==2.20.0
google-cloud-storage==2.16.0
google-crc32c==1.5.0
google-resumable-media==2.7.0
googleapis-common-protos==1.63.0
greenlet==3.0.3
grpc-google-iam-v1==0.13.0
grpcio==1.64.0
grpcio-status==1.62.2
h11==0.14.0
httpcore==1.0.5
httplib2==0.22.0
httpx==0.27.0
httpx-sse==0.4.0
huggingface-hub==0.23.1
humanfriendly==10.0
idna==3.7
intel-openmp==2021.4.0
iopath==0.1.10
ipykernel==6.29.5
ipython==8.18.1
jedi==0.19.1
Jinja2==3.1.4
joblib==1.4.2
jsonpatch==1.33
jsonpath-python==1.0.6
jsonpointer==2.4
jsonschema==4.22.0
jsonschema-specifications==2023.12.1
jupyter_client==8.6.2
jupyter_core==5.7.2
kiwisolver==1.4.5
langchain==0.2.6
langchain-cli==0.0.22
langchain-community==0.2.6
langchain-core==0.2.10
langchain-google-community==1.0.4
langchain-google-vertexai==1.0.4
langchain-mistralai==0.1.9
langchain-openai==0.1.7
langchain-text-splitters==0.2.0
langdetect==1.0.9
langserve==0.2.0
langsmith==0.1.82
layoutparser==0.3.4
libcst==1.3.1
lxml==5.2.2
markdown-it-py==3.0.0
MarkupSafe==2.1.5
marshmallow==3.21.2
matplotlib==3.9.0
matplotlib-inline==0.1.7
mdurl==0.1.2
-e git+https://github.com/adeo/lmit-ds-chatgen.git@83cc608303f518081f3e9e142330c9c9c1c4165d#egg=merlyno
mkl==2021.4.0
mpmath==1.3.0
multidict==6.0.5
mypy-extensions==1.0.0
nest-asyncio==1.6.0
networkx==3.2.1
nltk==3.8.1
numpy==1.26.4
oauthlib==3.2.2
omegaconf==2.3.0
onnx==1.16.0
onnxruntime==1.15.1
openai==1.30.1
opencv-python==4.9.0.80
opencv-python-headless==4.10.0.84
ordered-set==4.1.0
orjson==3.10.3
packaging==23.2
pandas==2.2.2
parso==0.8.4
pathspec==0.12.1
pdf2image==1.17.0
pdfminer.six==20231228
pdfplumber==0.11.0
pikepdf==8.15.1
pillow==10.3.0
pillow_heif==0.16.0
platformdirs==4.2.2
portalocker==2.8.2
prompt_toolkit==3.0.47
proto-plus==1.23.0
protobuf==4.25.3
psutil==6.0.0
pure-eval==0.2.2
pyarrow==16.1.0
pyasn1==0.6.0
pyasn1_modules==0.4.0
pycocotools==2.0.7
pycparser==2.22
pydantic==1.10.15
pydeck==0.9.1
Pygments==2.18.0
PyJWT==2.8.0
pyparsing==3.1.2
pypdf==4.2.0
pypdfium2==4.30.0
pyproject-toml==0.0.10
pyreadline3==3.4.1
pytesseract==0.3.10
python-dateutil==2.9.0.post0
python-docx==1.1.2
python-dotenv==1.0.1
python-iso639==2024.4.27
python-magic==0.4.27
python-multipart==0.0.9
pytz==2024.1
pywin32==306
PyYAML==6.0.1
pyzmq==26.0.3
rapidfuzz==3.9.1
referencing==0.35.1
regex==2024.5.15
requests==2.32.2
requests-oauthlib==2.0.0
rich==13.7.1
rpds-py==0.18.1
rsa==4.9
safetensors==0.4.3
scipy==1.13.0
shapely==2.0.4
shellingham==1.5.4
six==1.16.0
smmap==5.0.1
sniffio==1.3.1
soupsieve==2.5
SQLAlchemy==2.0.30
sse-starlette==1.8.2
stack-data==0.6.3
starlette==0.37.2
streamlit==1.34.0
sympy==1.12
tabulate==0.9.0
tbb==2021.12.0
tenacity==8.3.0
tiktoken==0.7.0
timm==1.0.3
tokenizers==0.19.1
toml==0.10.2
tomli==2.0.1
tomlkit==0.12.5
toolz==0.12.1
torch==2.3.0
torchvision==0.18.0
tornado==6.4
tqdm==4.66.4
traitlets==5.14.3
transformers==4.41.0
typer==0.9.4
typing-inspect==0.9.0
typing_extensions==4.11.0
tzdata==2024.1
unstructured==0.12.5
unstructured-client==0.22.0
unstructured-inference==0.7.23
unstructured.pytesseract==0.3.12
uritemplate==4.1.1
urllib3==2.2.1
uvicorn==0.23.2
watchdog==4.0.0
wcwidth==0.2.13
wrapt==1.16.0
yarl==1.9.4
zipp==3.17.0