Add safety preprocessing and routing to ReactToMe

src/agent/profiles/base.py

@@ -1,14 +1,19 @@
-from typing import Annotated, TypedDict
+from typing import Annotated, Literal, TypedDict
 
 from langchain_core.embeddings import Embeddings
 from langchain_core.language_models.chat_models import BaseChatModel
 from langchain_core.messages import BaseMessage
 from langchain_core.runnables import Runnable, RunnableConfig
 from langgraph.graph.message import add_messages
 
-from agent.tasks.rephrase import create_rephrase_chain
 from tools.external_search.state import SearchState, WebSearchResult
 from tools.external_search.workflow import create_search_workflow
+from tools.preprocessing.state import PreprocessingState
+from tools.preprocessing.workflow import create_preprocessing_workflow
+
+SAFETY_SAFE: Literal["true"] = "true"
+SAFETY_UNSAFE: Literal["false"] = "false"
+DEFAULT_LANGUAGE: str = "English"
 
 
 class AdditionalContent(TypedDict, total=False):
@@ -20,39 +25,50 @@ class InputState(TypedDict, total=False):
 
 
 class OutputState(TypedDict, total=False):
-    answer: str  # primary LLM response that is streamed to the user
+    answer: str  #  LLM response streamed to the user
     additional_content: AdditionalContent  # sends on graph completion
 
 
 class BaseState(InputState, OutputState, total=False):
-    rephrased_input: str  # LLM-generated query from user input
+    rephrased_input: (
+        str  # contextualized, LLM-generated standalone query from user input
+    )
     chat_history: Annotated[list[BaseMessage], add_messages]
+    safety: str  # LLM-assessed safety level of the user input
+    reason_unsafe: str
 
 
 class BaseGraphBuilder:
-    # NOTE: Anything that is common to all graph builders goes here
 
     def __init__(
         self,
         llm: BaseChatModel,
         embedding: Embeddings,
     ) -> None:
-        self.rephrase_chain: Runnable = create_rephrase_chain(llm)
+        self.preprocessing_workflow: Runnable = create_preprocessing_workflow(llm)
         self.search_workflow: Runnable = create_search_workflow(llm)
 
     async def preprocess(self, state: BaseState, config: RunnableConfig) -> BaseState:
-        rephrased_input: str = await self.rephrase_chain.ainvoke(
-            {
-                "user_input": state["user_input"],
-                "chat_history": state["chat_history"],
-            },
+        result: PreprocessingState = await self.preprocessing_workflow.ainvoke(
+            PreprocessingState(
+                user_input=state["user_input"],
+                chat_history=state.get("chat_history", []),
+            ),
             config,
         )
-        return BaseState(rephrased_input=rephrased_input)
+        mapped_state = BaseState(
+            rephrased_input=result.get("rephrased_input", ""),
+            safety=result.get("safety", SAFETY_SAFE),
+            reason_unsafe=result.get("reason_unsafe", ""),
+        )
+        return BaseState(**state, **mapped_state)
 
     async def postprocess(self, state: BaseState, config: RunnableConfig) -> BaseState:
         search_results: list[WebSearchResult] = []
-        if config["configurable"]["enable_postprocess"]:
+        if (
+            state.get("safety") == SAFETY_SAFE
+            and config["configurable"]["enable_postprocess"]
+        ):
             result: SearchState = await self.search_workflow.ainvoke(
                 SearchState(
                     input=state["rephrased_input"],
@@ -62,5 +78,6 @@ async def postprocess(self, state: BaseState, config: RunnableConfig) -> BaseSta
             )
             search_results = result["search_results"]
         return BaseState(
-            additional_content=AdditionalContent(search_results=search_results)
+            **state,
+            additional_content=AdditionalContent(search_results=search_results),
         )

src/agent/profiles/react_to_me.py

@@ -1,12 +1,14 @@
-from typing import Any
+from typing import Any, Literal
 
 from langchain_core.embeddings import Embeddings
 from langchain_core.language_models.chat_models import BaseChatModel
 from langchain_core.messages import AIMessage, HumanMessage
 from langchain_core.runnables import Runnable, RunnableConfig
 from langgraph.graph.state import StateGraph
 
-from agent.profiles.base import BaseGraphBuilder, BaseState
+from agent.profiles.base import (DEFAULT_LANGUAGE, SAFETY_SAFE, SAFETY_UNSAFE,
+                                 BaseGraphBuilder, BaseState)
+from agent.tasks.unsafe_answer import create_unsafe_answer_generator
 from retrievers.reactome.rag import create_reactome_rag
 
 
@@ -23,6 +25,9 @@ def __init__(
         super().__init__(llm, embedding)
 
         # Create runnables (tasks & tools)
+        streaming_llm = llm.model_copy(update={"streaming": True})
+
+        self.unsafe_answer_generator = create_unsafe_answer_generator(streaming_llm)
         self.reactome_rag: Runnable = create_reactome_rag(
             llm, embedding, streaming=True
         )
@@ -32,36 +37,84 @@ def __init__(
         # Set up nodes
         state_graph.add_node("preprocess", self.preprocess)
         state_graph.add_node("model", self.call_model)
+        state_graph.add_node("generate_unsafe_response", self.generate_unsafe_response)
         state_graph.add_node("postprocess", self.postprocess)
         # Set up edges
         state_graph.set_entry_point("preprocess")
-        state_graph.add_edge("preprocess", "model")
+        state_graph.add_conditional_edges(
+            "preprocess",
+            self.proceed_with_research,
+            {"Continue": "model", "Finish": "generate_unsafe_response"},
+        )
         state_graph.add_edge("model", "postprocess")
+        state_graph.add_edge("generate_unsafe_response", "postprocess")
         state_graph.set_finish_point("postprocess")
 
         self.uncompiled_graph: StateGraph = state_graph
 
+    async def proceed_with_research(
+        self, state: ReactToMeState
+    ) -> Literal["Continue", "Finish"]:
+        return "Continue" if state.get("safety") == SAFETY_SAFE else "Finish"
+
+    async def generate_unsafe_response(
+        self, state: ReactToMeState, config: RunnableConfig
+    ) -> ReactToMeState:
+        final_answer_message = await self.unsafe_answer_generator.ainvoke(
+            {
+                "language": state.get("detected_language", DEFAULT_LANGUAGE),
+                "user_input": state.get("rephrased_input", state["user_input"]),
+                "reason_unsafe": state.get("reason_unsafe", ""),
+            },
+            config,
+        )
+
+        final_answer = (
+            final_answer_message.content
+            if hasattr(final_answer_message, "content")
+            else str(final_answer_message)
+        )
+
+        updated_state = dict(state)
+        updated_state.update(
+            chat_history=[
+                HumanMessage(state["user_input"]),
+                (
+                    final_answer_message
+                    if hasattr(final_answer_message, "content")
+                    else AIMessage(final_answer)
+                ),
+            ],
+            answer=final_answer,
+            safety=SAFETY_UNSAFE,
+            additional_content={"search_results": []},
+        )
+        return ReactToMeState(**updated_state)
+
     async def call_model(
         self, state: ReactToMeState, config: RunnableConfig
     ) -> ReactToMeState:
         result: dict[str, Any] = await self.reactome_rag.ainvoke(
             {
                 "input": state["rephrased_input"],
+                "expanded_queries": state.get("expanded_queries", []),
                 "chat_history": (
-                    state["chat_history"]
-                    if state["chat_history"]
+                    state.get("chat_history")
+                    if state.get("chat_history")
                     else [HumanMessage(state["user_input"])]
                 ),
             },
             config,
         )
-        return ReactToMeState(
+        updated_state = dict(state)
+        updated_state.update(
             chat_history=[
                 HumanMessage(state["user_input"]),
                 AIMessage(result["answer"]),
             ],
             answer=result["answer"],
         )
+        return ReactToMeState(**updated_state)
 
 
 def create_reactome_graph(

src/agent/tasks/safety_checker.py

@@ -3,28 +3,57 @@
 from langchain_core.runnables import Runnable
 from pydantic import BaseModel, Field
 
-safety_check_message = """
-You are an expert grader with a strong understanding of ethical guidelines and responsible AI usage.
-
-Your task is to determine whether a user-submitted question is appropriate and not harmful.
-Provide a binary output as either:
-Yes: The question is appropriate and not harmful.
-No: The question is harmful, offensive, inappropriate, or unethical.
-"""
-
-safety_check_prompt = ChatPromptTemplate.from_messages(
-    [
-        ("system", safety_check_message),
-        ("human", "User question: \n\n {input}"),
-    ]
-)
-
 
 class SafetyCheck(BaseModel):
-    binary_score: str = Field(
-        description="Indicates whether the question is appropriate and related to molecular biology. Expected values: 'Yes' or 'No'."
+    safety: str = Field(
+        description="Indicates whether the question is appropriate and related to molecular biology. Expected values: 'true' or 'false'."
+    )
+    reason_unsafe: str = Field(
+        description="If 'safety' is false, briefly state the reason; if 'safety' is true, leave this field empty."
     )
 
 
 def create_safety_checker(llm: BaseChatModel) -> Runnable:
-    return safety_check_prompt | llm.with_structured_output(SafetyCheck)
+    """
+    Create a safety checker chain.
+
+    Args:
+        llm: Language model to use
+
+    Returns:
+        Runnable that takes rephrased_input and returns SafetyCheck
+    """
+    safety_check_message = """
+You are an expert scientific assistant. You have advanced training in scientific ethics, dual-use assessment, and responsible AI.
+
+Tasks:
+
+1. Safety & Appropriateness Check
+    - Assess the question and determine if it is safe and appropriate for responsible AI use.
+    - The question and any plausible answer to it must NOT be harmful, offensive, unethical, or violate scientific or ethical guidelines.
+    - The question or its likely answers must NOT request, describe, or explore how to carry out harmful, illegal, dangerous, or dual-use activities (such as modifying pathogens, increasing infectivity, or other forms of misuse)—even if the scenario is hypothetical, fictional, or indirect.
+    - The question must NOT request personal, medical, legal, or other types of advice outside the scope of scientific knowledge.
+    - If a question is ambiguous or could plausibly be used for harm, treat it as unsafe.
+    - Treat hypothetical, fictional, or made-up scenarios with the same level of scrutiny as real-world questions.
+
+2. Reactome Relevance Check
+    - Determine if the question is relevant to biology, life sciences, molecular biology, or related topics.
+    - Mark questions as not relevant if they are about unrelated topics (such as programming, math, history, trivia, etc.).
+
+IMPORTANT:
+    - If the standalone question is unsafe or not relevant return "safety": "false".
+    - If the standalone question is both safe **and** relevant, return "safety": "true".
+
+Return only a JSON object in the following format:
+    "safety": "true" or "false", // Use string, not boolean. Mark as "false" if unsafe OR not relevant.
+    "reason_unsafe": "..." // If 'safety' is false, briefly state the reason
+"""
+
+    prompt = ChatPromptTemplate.from_messages(
+        [
+            ("system", safety_check_message),
+            ("human", "User question: \n\n {rephrased_input}"),
+        ]
+    )
+
+    return prompt | llm.with_structured_output(SafetyCheck)

src/agent/tasks/unsafe_answer.py

@@ -0,0 +1,46 @@
+from langchain_core.language_models.chat_models import BaseChatModel
+from langchain_core.prompts import ChatPromptTemplate
+from langchain_core.runnables import Runnable
+
+
+def create_unsafe_answer_generator(llm: BaseChatModel) -> Runnable:
+    """
+    Create an unsafe answer generator chain.
+
+    Args:
+        llm: Language model to use.
+
+    Returns:
+        Runnable that generates refusal messages for unsafe or out-of-scope queries.
+    """
+    system_prompt = """
+    You are an expert scientific assistant operating under the React-to-Me platform. React-to-Me helps both experts and non-experts explore molecular biology using trusted data from the Reactome database.
+
+You have advanced training in scientific ethics, dual-use research concerns, and responsible AI use.
+
+You will receive three inputs: 
+1. The user's question.
+2. A system-generated variable called `reason_unsafe`, which explains why the question cannot be answered.
+3. The user's preferred language (as a language code or name).
+
+Your task is to clearly, respectfully, and firmly explain to the user *why* their question cannot be answered, based solely on the `reason_unsafe` input. Do **not** attempt to answer, rephrase, or guide the user toward answering the original question.
+
+You must:
+- Respond in the user’s preferred language.
+- Politely explain the refusal, grounded in the `reason_unsafe`.
+- Emphasize React-to-Me’s mission: to support responsible exploration of molecular biology through trusted databases.
+- Suggest examples of appropriate topics (e.g., protein function, pathways, gene interactions using Reactome/UniProt).
+
+You must not provide any workaround, implicit answer, or redirection toward unsafe content.
+"""
+    prompt = ChatPromptTemplate.from_messages(
+        [
+            ("system", system_prompt),
+            (
+                "user",
+                "Language:{language}\n\nQuestion:{user_input}\n\n Reason for unsafe or out of scope: {reason_unsafe}",
+            ),
+        ]
+    )
+
+    return prompt | llm

src/tools/preprocessing/__init__.py

@@ -0,0 +1,6 @@
+"""
+Preprocessing utilities with reusable workflows and state definitions.
+"""
+
+from .state import PreprocessingState  # noqa: F401
+from .workflow import create_preprocessing_workflow  # noqa: F401

src/tools/preprocessing/state.py

@@ -0,0 +1,18 @@
+from typing import TypedDict
+
+from langchain_core.messages import BaseMessage
+
+
+class PreprocessingState(TypedDict, total=False):
+    """State for the preprocessing workflow."""
+
+    # Inputs
+    user_input: str
+    chat_history: list[BaseMessage]
+
+    # Task outputs
+    rephrased_input: str
+    safety: str
+    reason_unsafe: str
+    expanded_queries: list[str]
+    detected_language: str