istari-core 0.1.1

Infer user intent states from behavioral event streams

Istari

Istari is a Python library that infers user intent states from raw behavioral event streams and exposes them as a structured, machine-readable layer for CRO systems, personalization engines, and agentic AI workflows.

Instead of treating user behavior as isolated events or funnels, Istari models sessions as continuous intent trajectories over time.

What Problem Istari Solves

Modern products collect events like:

• page views
• scroll depth
• clicks
• add to cart
• remove from cart
• time gaps
• navigation loops
• rage clicks (Clarity)
• dead clicks (Clarity)

But downstream systems still reason in crude terms like funnels and conversion rates.

Istari sits between raw analytics and decision-making systems and answers:

• What is the user trying to do right now?
• Are they exploring, comparing, hesitating, or ready to act?
• What friction or uncertainty is blocking progress?
• How intent is evolving over the session?

Core Abstraction

Istari introduces a first-class abstraction called an Intent State.

An intent state is:

• time-aware: associated with timestamps
• probabilistic: has confidence scores
• explainable: includes attribution data
• composable: can be combined across domains

Example intent states:

• browsing
• evaluating_options
• price_sensitive
• trust_seeking
• purchase_ready
• abandonment_risk

High-Level Flow

1. Raw events are normalized into a canonical schema
2. Temporal patterns and transitions are extracted
3. Intent hypotheses are scored
4. A state machine produces the most likely intent trajectory
5. Outputs are exposed to CRO rules or agentic systems

Design Goals

• Python-first, backend friendly
• Deterministic core with optional ML layers
• Explainability by default
• Domain-adaptable without retraining
• Open-core friendly architecture

Installation

pip install istari-core

For development:

git clone https://github.com/istari/istari.git
cd istari
pip install -e .

Quick Start

from datetime import datetime, timedelta, timezone
from istari.core.events import Event
from istari.core.session import Session
from istari.inference.rules import RuleBasedInference
from istari.inference.heuristics import BrowsingRule, PurchaseReadyRule

# Create a session
session = Session(
    session_id="session_123",
    user_id="user_456",
    started_at=datetime.now(timezone.utc),
)

# Add events
session.add_event(Event(
    event_type="page_view",
    timestamp=datetime.now(timezone.utc),
    user_id="user_456",
    session_id="session_123",
    properties={"page": "/products"},
))

# Infer intent state
inference = RuleBasedInference()
inference.add_rule(BrowsingRule())
inference.add_rule(PurchaseReadyRule())

intent_state = inference.infer(session)
print(f"Intent: {intent_state.state_type}")
print(f"Confidence: {intent_state.confidence:.2%}")

Microsoft Clarity Integration

Istari includes first-class support for Microsoft Clarity behavioral signals. Clarity events are converted into Istari's canonical format and mapped to intent signals:

from istari.sources.clarity import ClaritySource

# Initialize Clarity source
clarity_source = ClaritySource()

# Parse Clarity events/exports
clarity_events = [
    {
        "event": "rage_click",
        "timestamp": 1234567890000,
        "userId": "user_123",
        "sessionId": "session_456",
        "clickCount": 5,
    },
    # ... more events
]

# Parse and extract signals
events, signals = clarity_source.process(clarity_events)

# Signals are automatically mapped:
# - rage_click → friction.high
# - dead_click → intent.confusion
# - scroll → content_engagement
# - excessive_hover → hesitation

Clarity Signal Mappings

Clarity Signal	Istari Signal	Intent Impact
Rage clicks	friction.high	Contributes to abandonment_risk
Dead clicks	intent.confusion	Contributes to hesitating
Scroll depth	content_engagement	Contributes to browsing
Quick back nav	dissatisfaction	Contributes to abandonment_risk
Excessive hover	hesitation	Contributes to hesitating

Architecture

Core Modules

• core/: Event normalization, session modeling, intent states, transitions, scoring
• schemas/: Event schema normalization (base, ecommerce, web)
• inference/: Rule-based inference, heuristics, state machine, confidence calculation
• signals/: Signal extraction (dwell, navigation, comparison, friction, price)
• explainability/: Attribution calculation, narrative generation, summaries
• plugins/: Plugin system for extending inference capabilities
• sources/: Event source integrations (Clarity, etc.)
• integrations/: Analytics platform integrations (Mixpanel, Amplitude, Segment)

Event Sources vs Integrations

• sources/: Behavioral signal sources (like Clarity) that provide frontend behavioral data
• integrations/: Analytics platform integrations for event ingestion

Open-Source vs Proprietary

Open-source core:

• Event normalization
• Session modeling
• Intent state definitions
• Rule-based inference
• Explainability primitives
• Plugin interfaces
• Clarity integration

Proprietary extensions (planned):

• Learned intent models
• Vertical-specific heuristics
• Advanced uncertainty modeling
• Real-time streaming inference
• Deep analytics integrations

Examples

See the examples/ directory for:

• basic_inference.py: Basic intent inference
• ecommerce_session.py: Full e-commerce session analysis
• explain_intent.py: Intent explanation and narratives
• clarity_integration.py: Microsoft Clarity integration example

Documentation

• Concepts
• Intent States
• Schemas
• Explainability
• Plugins

License

Apache License 2.0 - see LICENSE file for details.

Contributing

Contributions welcome! Please see our contributing guidelines (coming soon).