WhyTrend

Open Source Framework for Explainable Time Series Analysis

WhyTrend detects anomalies, change points, and trend shifts in time series — then automatically explains why they happened using external context and LLMs.

If this project is useful to you, consider giving it a star on GitHub — it helps others discover the project. Forks and pull requests are welcome.

Features

• Fluent Pipeline API for source → detection → collection → ranking → explanation
• Pluggable sources, detectors, collectors, rankers, and LLM providers
• Structured Report output (JSON and Markdown)
• Async collectors and LLM calls
• Works offline with MockLLMProvider and local models via OllamaExplainer

Installation

git clone https://github.com/AlexProvatorov/WhyTrend.git
cd WhyTrend
python -m venv .venv
source .venv/bin/activate
pip install -e ".[dev]"

Optional extras

pip install -e ".[openai]"      # OpenAI API
pip install -e ".[trends]"      # Google Trends
pip install -e ".[prophet]"       # Prophet detector
pip install -e ".[ruptures]"      # change-point detector
pip install -e ".[river]"         # online / streaming detector
pip install -e ".[ranking]"       # Embedding ranker
pip install -e ".[all]"           # everything

Quickstart (CSV, no API keys)

from whytrend import (
    BM25Ranker,
    CSVSource,
    LLMExplainer,
    MockLLMProvider,
    Pipeline,
    ZScoreDetector,
)

pipeline = (
    Pipeline(window_days=3)
    .add_source(CSVSource("tests/fixtures/python_interest.csv", keyword="Python"))
    .add_detector(ZScoreDetector(threshold=1.0))
    .add_ranker(BM25Ranker(top_k=5))
    .add_explainer(LLMExplainer(MockLLMProvider()))
)

report = pipeline.run()
print(report.executive_summary)
print(report.to_markdown())

Run the full demo:

pip install -e ".[dev]"
python examples/mvp_demo.py

Production-style example

from whytrend import (
    GoogleTrends,
    OpenAIExplainer,
    Pipeline,
    ProphetDetector,
)
from whytrend.collectors import (
    GitHubReleasesCollector,
    GoogleNewsCollector,
    HackerNewsCollector,
    RSSFeedCollector,
    RedditCollector,
    StackOverflowCollector,
    WikipediaCollector,
)
from whytrend.rankers import BM25Ranker

pipeline = (
    Pipeline()
    .add_source(GoogleTrends("Python"))
    .add_detector(ProphetDetector())
    .add_collector(GoogleNewsCollector())
    .add_collector(HackerNewsCollector())
    .add_collector(RedditCollector())  # REDDIT_CLIENT_ID + REDDIT_CLIENT_SECRET
    .add_collector(GitHubReleasesCollector())  # optional GITHUB_TOKEN
    .add_collector(StackOverflowCollector())  # optional STACKEXCHANGE_KEY
    .add_collector(
        RSSFeedCollector(
            [
                "https://blog.python.org/feeds/posts/default",
                "https://pyfound.blogspot.com/feeds/posts/default",
            ]
        )
    )
    .add_collector(WikipediaCollector())
    .add_ranker(BM25Ranker())
    .add_explainer(OpenAIExplainer())  # OPENAI_API_KEY env var or api_key="..."
)

report = pipeline.run()
print(report.executive_summary)

Use OllamaExplainer(model="llama3.2") for a local LLM instead of OpenAI.

Reddit credentials (create at https://www.reddit.com/prefs/apps):

export REDDIT_CLIENT_ID="..."
export REDDIT_CLIENT_SECRET="..."

Or pass them explicitly:

RedditCollector(client_id="...", client_secret="...", subreddits=["Python", "MachineLearning"])

GitHub Releases works without a token for light use. For higher rate limits:

export GITHUB_TOKEN="ghp_..."

GitHubReleasesCollector(token="ghp_...", repos=["python/cpython"])

Stack Overflow works without a key for light use. For a higher daily quota (register at https://stackapps.com/):

export STACKEXCHANGE_KEY="..."

StackOverflowCollector(api_key="...", site="stackoverflow")

Custom RSS/Atom feeds (keyword + time-window filtered):

RSSFeedCollector(
    [
        "https://blog.python.org/feeds/posts/default",
        "https://hnrss.org/frontpage",
    ]
)

Architecture

Source → Detector → Event Builder → Collectors → Ranker → Explainer → Report

Choosing a detector

from whytrend import RiverDetector, RupturesDetector

RupturesDetector(algorithm="pelt", model="rbf", penalty=10.0)
RiverDetector(model="gaussian", threshold=0.95, min_points=10)

Roadmap

Core MVP is in place. Next focus: integrations and ecosystem.

v0.2 — More collectors

• Google News
• Reddit
• GitHub Releases
• RSS / Stack Overflow

v0.3 — More detectors

• Ruptures (change-point)
• River / streaming detectors

v0.4 — More LLM providers

• Anthropic, Gemini, DeepSeek
• Azure OpenAI, OpenRouter

v0.5 — Reports and DX

• HTML / PDF reports
• CLI (whytrend analyze ...)
• Plugin registry (entry points)

v0.6 — Ranking quality

• Hybrid ranker (BM25 + embeddings merged with RRF)
• Post-ranker evidence filter (relevance thresholds, stronger rerank, explicit verdicts like evidence_insufficient / correlation_only / likely_cause)

Track progress in GitHub Issues.

Development

make install   # install with detected tool (uv / poetry / pip)
make check     # ruff + format check + mypy + pytest

Supports the three common workflows:

Auto-detect order: uv → poetry → pip. Override anytime with TOOL=....

Useful targets:

make lint          # ruff check
make format        # ruff format + autofix
make format-check  # ruff format --check
make typecheck     # mypy
make test          # pytest
make help          # list all targets

Author

Alexander Provatorov — GitHub @AlexProvatorov

License

Licensed under the Apache License, Version 2.0.