fleet-memory/hindsight-api
Chris Bartholomew 8b1a46585d
Fix reflect based_on population and enforce full hierarchical retrieval (#421)
* Fix reflect based_on population and enforce full hierarchical retrieval

Problem 1: based_on field was incomplete
- search_observations results were never extracted into based_on, so
  observations used by the agent were invisible to callers
- search_mental_models and get_mental_model used non-existent fields
  (summary/description) instead of the actual content field, producing
  empty text in based_on entries
- A duplicate unreachable elif block for search_mental_models was dead
  code (the first identical condition always matched)

Problem 2: mental models could produce "I don't have information"
- When a bank has mental models, the agent's tool_choice forcing only
  covered iteration 0 (search_mental_models). Iterations 1+ were auto,
  allowing the LLM to short-circuit without ever searching observations
  or raw facts. Combined with the LOW budget prompt encouraging speed,
  this meant the agent would often stop after a single tool call.
- This created a self-reinforcing failure loop: if a mental model
  refresh produced "I don't have information" (e.g. due to the agent
  skipping recall), subsequent reflects would find that content and
  trust it, never searching deeper.

Fix: extend forced tool_choice to cover the full hierarchical retrieval
path before allowing auto mode:
- With mental models: search_mental_models(0) → search_observations(1)
  → recall(2) → auto(3+)
- Without mental models: search_observations(0) → recall(1) → auto(2+)

This matches the retrieval strategy documented in the system prompt and
ensures all three knowledge levels are always consulted. The agent still
has 2-3 auto iterations (with LOW budget, max_iterations=5) for
additional searches or calling done().

* Add Umami analytics tracking to docs site

Add conditional Umami script injection to docusaurus.config.ts and pass
UMAMI_URL/UMAMI_WEBSITE_ID env vars in the GitHub Pages deploy workflow.
The tracking script only loads when both env vars are set.
2026-02-23 10:13:19 +01:00
..
hindsight_api Fix reflect based_on population and enforce full hierarchical retrieval (#421) 2026-02-23 10:13:19 +01:00
tests feat: add ZeroEntropy reranker provider support (#420) 2026-02-23 10:12:32 +01:00
pyproject.toml misc: fix vertex/gemini errors and use it for ci tests (#414) 2026-02-20 22:35:38 +01:00
README.md feat(doc): add new config options and supported providers (#84) 2026-01-01 17:09:05 +01:00

Hindsight API

Memory System for AI Agents — Temporal + Semantic + Entity Memory Architecture using PostgreSQL with pgvector.

Hindsight gives AI agents persistent memory that works like human memory: it stores facts, tracks entities and relationships, handles temporal reasoning ("what happened last spring?"), and forms opinions based on configurable disposition traits.

Installation

pip install hindsight-api

Quick Start

Run the Server

# Set your LLM provider
export HINDSIGHT_API_LLM_PROVIDER=openai
export HINDSIGHT_API_LLM_API_KEY=sk-xxxxxxxxxxxx

# Start the server (uses embedded PostgreSQL by default)
hindsight-api

The server starts at http://localhost:8888 with:

  • REST API for memory operations
  • MCP server at /mcp for tool-use integration

Use the Python API

from hindsight_api import MemoryEngine

# Create and initialize the memory engine
memory = MemoryEngine()
await memory.initialize()

# Create a memory bank for your agent
bank = await memory.create_memory_bank(
    name="my-assistant",
    background="A helpful coding assistant"
)

# Store a memory
await memory.retain(
    memory_bank_id=bank.id,
    content="The user prefers Python for data science projects"
)

# Recall memories
results = await memory.recall(
    memory_bank_id=bank.id,
    query="What programming language does the user prefer?"
)

# Reflect with reasoning
response = await memory.reflect(
    memory_bank_id=bank.id,
    query="Should I recommend Python or R for this ML project?"
)

CLI Options

hindsight-api --help

# Common options
hindsight-api --port 9000          # Custom port (default: 8888)
hindsight-api --host 127.0.0.1     # Bind to localhost only
hindsight-api --workers 4          # Multiple worker processes
hindsight-api --log-level debug    # Verbose logging

Configuration

Configure via environment variables:

Variable Description Default
HINDSIGHT_API_DATABASE_URL PostgreSQL connection string pg0 (embedded)
HINDSIGHT_API_LLM_PROVIDER openai, anthropic, gemini, groq, ollama, lmstudio openai
HINDSIGHT_API_LLM_API_KEY API key for LLM provider -
HINDSIGHT_API_LLM_MODEL Model name gpt-4o-mini
HINDSIGHT_API_HOST Server bind address 0.0.0.0
HINDSIGHT_API_PORT Server port 8888

Example with External PostgreSQL

export HINDSIGHT_API_DATABASE_URL=postgresql://user:pass@localhost:5432/hindsight
export HINDSIGHT_API_LLM_PROVIDER=groq
export HINDSIGHT_API_LLM_API_KEY=gsk_xxxxxxxxxxxx

hindsight-api

Docker

docker run --rm -it -p 8888:8888 \
  -e HINDSIGHT_API_LLM_API_KEY=$OPENAI_API_KEY \
  -v $HOME/.hindsight-docker:/home/hindsight/.pg0 \
  ghcr.io/vectorize-io/hindsight:latest

MCP Server

For local MCP integration without running the full API server:

hindsight-local-mcp

This runs a stdio-based MCP server that can be used directly with MCP-compatible clients.

Key Features

  • Multi-Strategy Retrieval (TEMPR) — Semantic, keyword, graph, and temporal search combined with RRF fusion
  • Entity Graph — Automatic entity extraction and relationship tracking
  • Temporal Reasoning — Native support for time-based queries
  • Disposition Traits — Configurable skepticism, literalism, and empathy influence opinion formation
  • Three Memory Types — World facts, bank actions, and formed opinions with confidence scores

Documentation

Full documentation: https://hindsight.vectorize.io

License

Apache 2.0