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Retain: How Hindsight Stores Memories

When you call retain(), Hindsight transforms conversations and documents into structured, searchable memories that preserve meaning and context.

What Retain Does​

Your Content
     ↓
Extract Rich Facts
     ↓
Identify Entities
     ↓
Build Connections
     ↓
Searchable Memory Bank

Rich Fact Extraction​

Hindsight doesn't just store what was said — it captures why, how, and what it means.

What Gets Captured​

When you retain "Alice joined Google last spring and was thrilled about the research opportunities", Hindsight extracts:

The core facts:

  • Alice joined Google
  • This happened last spring

The emotions and meaning:

  • She was thrilled
  • It represented an important opportunity

The reasoning:

  • She chose it for the research opportunities

This rich extraction means you can later ask "Why did Alice join Google?" and get a meaningful answer, not just "she joined Google."

Preserving Context​

Traditional systems fragment information:

  • "Bob suggested Summer Vibes"
  • "Alice wanted something unique"
  • "They chose Beach Beats"

Hindsight preserves the full narrative:

  • "Alice and Bob discussed naming their summer party playlist. Bob suggested 'Summer Vibes' because it's catchy, but Alice wanted something unique. They ultimately decided on 'Beach Beats' for its playful tone."

This means search results include the full context, not disconnected fragments.

Two Types of Facts​

Hindsight distinguishes between world facts (about others) and experience (conversations and events):

TypeDescriptionExample
worldFacts about people, places, things"Alice works at Google"
experienceConversations and events"I recommended Python to Alice"

This separation is important for reflect() — the bank can reason about what it knows versus what happened in conversations.

Note: Opinions aren't created during retain() — only during reflect() when the bank forms beliefs.

Entity Recognition​

Hindsight automatically identifies and tracks entities — the people, organizations, and concepts that matter.

What Gets Recognized​

  • People: "Alice", "Dr. Smith", "Bob Chen"
  • Organizations: "Google", "MIT", "OpenAI"
  • Places: "Paris", "Central Park", "California"
  • Products & Concepts: "Python", "TensorFlow", "machine learning"

Entity Resolution​

The same entity mentioned different ways gets unified:

  • "Alice" + "Alice Chen" + "Alice C." → one person
  • "Bob" + "Robert Chen" → one person (nickname resolution)

Why it matters: You can ask "What do I know about Alice?" and get everything, even if she was mentioned as "Alice Chen" in some conversations.

Context-Aware Disambiguation​

If "Alice" appears with "Google" and "Stanford" multiple times, a new "Alice" mentioning those is likely the same person. Hindsight uses co-occurrence patterns to disambiguate common names.

Building Connections​

Memories aren't isolated — Hindsight creates a knowledge graph with four types of connections:

Entity Connections​

All facts mentioning the same entity are linked together.

Enables: "Tell me everything about Alice" → retrieves all Alice-related facts

Time-Based Connections​

Facts close in time are connected, with stronger links for closer dates.

Enables: "What else happened around then?" → finds contextually related events

Meaning-Based Connections​

Semantically similar facts are linked, even if they use different words.

Enables: "Tell me about similar topics" → finds thematically related information

Causal Connections​

Cause-effect relationships are explicitly tracked.

Enables: "Why did this happen?" → trace reasoning chains Example: "Alice felt burned out" ← caused by ← "She worked 80-hour weeks"

Understanding Time​

Hindsight tracks two temporal dimensions:

When It Happened​

For events (meetings, trips, milestones), Hindsight records when they occurred.

  • "Alice got married in June 2024" → occurred in June 2024

For general facts (preferences, characteristics), there's no specific occurrence time.

  • "Alice prefers Python" → ongoing preference

When You Learned It​

Hindsight also tracks when you told it each fact.

Why both?

Imagine in January 2025, someone tells you "Alice got married in June 2024":

  • Historical queries work: "What did Alice do in 2024?" → finds the marriage
  • Recency ranking works: Recent mentions get priority in search
  • Temporal reasoning works: "What happened before her marriage?" → finds earlier events

Without this distinction, old information would either be unsearchable by date or treated as irrelevant.

Entity Observations​

As facts accumulate about an entity, Hindsight synthesizes observations — high-level summaries that capture what's known:

From multiple facts:

  • "Alice works at Google"
  • "Alice is a software engineer"
  • "Alice specializes in ML"

Hindsight creates:

  • "Alice is a software engineer at Google specializing in ML"

Why it helps: You can quickly understand an entity without reading through dozens of individual facts.

What You Get​

After retain() completes:

  • Structured facts that preserve meaning, emotions, and reasoning
  • Unified entities that resolve different name variations
  • Knowledge graph with entity, temporal, semantic, and causal links
  • Temporal grounding for both historical and recency-based queries
  • Background processing that generates entity summaries

All stored in your isolated memory bank, ready for recall() and reflect().

Next Steps​

  • Recall — How multi-strategy search retrieves relevant memories
  • Reflect — How personality influences reasoning and opinion formation
  • API Reference — Code examples for retaining memories