feature: adds the concept of now to the qa for temporal queries (#1685)

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## Description
 Adds the concept of now to the qa for temporal queries

## Type of Change
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- [ ] Bug fix (non-breaking change that fixes an issue)
- [ ] New feature (non-breaking change that adds functionality)
- [ ] Breaking change (fix or feature that would cause existing
functionality to change)
- [ ] Documentation update
- [x] Code refactoring
- [ ] Performance improvement
- [ ] Other (please specify):

## Screenshots/Videos (if applicable)
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## Pre-submission Checklist
<!-- Please check all boxes that apply before submitting your PR -->
- [ ] **I have tested my changes thoroughly before submitting this PR**
- [ ] **This PR contains minimal changes necessary to address the
issue/feature**
- [ ] My code follows the project's coding standards and style
guidelines
- [ ] I have added tests that prove my fix is effective or that my
feature works
- [ ] I have added necessary documentation (if applicable)
- [ ] All new and existing tests pass
- [ ] I have searched existing PRs to ensure this change hasn't been
submitted already
- [ ] I have linked any relevant issues in the description
- [ ] My commits have clear and descriptive messages

## DCO Affirmation
I affirm that all code in every commit of this pull request conforms to
the terms of the Topoteretes Developer Certificate of Origin.

cognee/infrastructure/llm/prompts/extract_query_time.txt

@@ -1,15 +1,13 @@
-For the purposes of identifying timestamps in a query, you are tasked with extracting relevant timestamps from the query.
+You are tasked with identifying relevant time periods where the answer to a given query should be searched.
-## Timestamp requirements
+Current date is:  `{{ time_now }}`. Determine relevant period(s) and return structured intervals.
-- If the query contains interval extrack both starts_at and ends_at  properties
+
-- If the query contains an instantaneous timestamp, starts_at and ends_at should be the same
+Extraction rules:
-- If the query its open-ended (before 2009 or after 2009), the corresponding non defined end of the time should be none
+
-    -For example: "before 2009" -- starts_at: None, ends_at: 2009 or  "after 2009" -- starts_at: 2009, ends_at: None
+1. Query without specific timestamp: use the time period with starts_at set to None and ends_at set to now.
-- Put always the data that comes first in time as starts_at and the timestamps that comes second in time as ends_at
+2. Explicit time intervals: If the query specifies a range (e.g., from 2010 to 2020, between January and March 2023), extract both start and end dates. Always assign the earlier date to starts_at and the later date to ends_at.
-- If starts_at or ends_at cannot be extracted both of them has to be None
+3. Single timestamp: If the query refers to one specific moment (e.g., in 2015, on March 5, 2022), set starts_at and ends_at to that same timestamp.
-## Output Format
+4. Open-ended time references: For phrases such as "before X" or "after X", represent the unspecified side as None. For example: before 2009 → starts_at: None, ends_at: 2009; after 2009 → starts_at: 2009, ends_at: None.
-Your reply should be a JSON: list of dictionaries with the following structure:
+5. Current-time references ("now", "current", "today"): If the query explicitly refers to the present, set both starts_at and ends_at to now (the ingestion timestamp).
-```python
+6. "Who is" and "Who was" questions: These imply a general identity or biographical inquiry without a specific temporal scope. Set both starts_at and ends_at to None.
-class QueryInterval(BaseModel):
+7. Ordering rule: Always ensure the earlier date is assigned to starts_at and the later date to ends_at.
-    starts_at: Optional[Timestamp] = None
+8. No temporal information: If no valid or inferable time reference is found, set both starts_at and ends_at to None.
-    ends_at: Optional[Timestamp] = None
-```

cognee/modules/retrieval/temporal_retriever.py

@@ -1,7 +1,7 @@
 import os
 import asyncio
 from typing import Any, Optional, List, Type
-
+from datetime import datetime
 
 from operator import itemgetter
 from cognee.infrastructure.databases.vector import get_vector_engine
@@ -79,7 +79,11 @@ class TemporalRetriever(GraphCompletionRetriever):
         else:
             base_directory = None
 
-        system_prompt = render_prompt(prompt_path, {}, base_directory=base_directory)
+        time_now = datetime.now().strftime("%d-%m-%Y")
+
+        system_prompt = render_prompt(
+            prompt_path, {"time_now": time_now}, base_directory=base_directory
+        )
 
         interval = await LLMGateway.acreate_structured_output(query, system_prompt, QueryInterval)
 
@@ -108,8 +112,6 @@ class TemporalRetriever(GraphCompletionRetriever):
 
         graph_engine = await get_graph_engine()
 
-        triplets = []
-
         if time_from and time_to:
             ids = await graph_engine.collect_time_ids(time_from=time_from, time_to=time_to)
         elif time_from:

examples/python/temporal_example.py

@@ -77,6 +77,7 @@ async def main():
         "What happened between 2000 and 2006?",
         "What happened between 1903 and 1995, I am interested in the Selected Works of Arnulf Øverland Ole Peter Arnulf Øverland?",
         "Who is Attaphol Buspakom Attaphol Buspakom?",
+        "Who was Arnulf Øverland?",
     ]
 
     for query_text in queries: