fleet-memory/CLAUDE.md

CLAUDE.md

This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.

Project Overview

Hindsight is an agent memory system that provides long-term memory for AI agents using biomimetic data structures. Memories are organized as:

• World facts: General knowledge ("The sky is blue")
• Experience facts: Personal experiences ("I visited Paris in 2023")
• Mental models: Consolidated knowledge synthesized from facts ("User prefers functional programming patterns")

Development Commands

API Server (Python/FastAPI)

# Start API server (loads .env automatically)
./scripts/dev/start-api.sh

# Run all tests (parallelized with pytest-xdist)
cd hindsight-api && uv run pytest tests/

# Run specific test file
cd hindsight-api && uv run pytest tests/test_http_api_integration.py -v

# Run single test function
cd hindsight-api && uv run pytest tests/test_retain.py::test_retain_simple -v

# Lint and format
cd hindsight-api && uv run ruff check .
cd hindsight-api && uv run ruff format .

# Type checking (uses ty - extremely fast type checker from Astral)
cd hindsight-api && uv run ty check hindsight_api/

Control Plane (Next.js)

./scripts/dev/start-control-plane.sh
# Or manually:
cd hindsight-control-plane && npm run dev

Documentation Site (Docusaurus)

./scripts/dev/start-docs.sh

Generating Clients/OpenAPI

# Regenerate OpenAPI spec after API changes (REQUIRED after changing endpoints)
./scripts/generate-openapi.sh

# Regenerate all client SDKs (Python, TypeScript, Rust)
./scripts/generate-clients.sh

Benchmarks

./scripts/benchmarks/run-longmemeval.sh
./scripts/benchmarks/run-locomo.sh
./scripts/benchmarks/start-visualizer.sh  # View results at localhost:8001

Architecture

Monorepo Structure

• hindsight-api/: Core FastAPI server with memory engine (Python, uv)
• hindsight/: Embedded Python bundle (hindsight-all package)
• hindsight-control-plane/: Admin UI (Next.js, npm)
• hindsight-cli/: CLI tool (Rust, cargo, uses progenitor for API client)
• hindsight-clients/: Generated SDK clients (Python, TypeScript, Rust)
• hindsight-docs/: Docusaurus documentation site
• hindsight-integrations/: Framework integrations (LiteLLM, OpenAI)
• hindsight-dev/: Development tools and benchmarks

Core Engine (hindsight-api/hindsight_api/engine/)

• memory_engine.py: Main orchestrator (~170KB) for retain/recall/reflect operations
• llm_wrapper.py: LLM abstraction supporting OpenAI, Anthropic, Gemini, Groq, Ollama, LM Studio
• embeddings.py: Embedding generation (local sentence-transformers or TEI)
• cross_encoder.py: Reranking (local or TEI)
• entity_resolver.py: Entity extraction and normalization
• query_analyzer.py: Query intent analysis

retain/: Memory ingestion pipeline

• orchestrator.py: Coordinates the retain flow
• fact_extraction.py: LLM-based fact extraction from content
• link_utils.py: Entity link creation and management

search/: Multi-strategy retrieval

• retrieval.py: Main retrieval orchestrator
• graph_retrieval.py: Entity/relationship graph traversal
• mpfp_retrieval.py: Multi-Path Fact Propagation retrieval
• fusion.py: Reciprocal rank fusion for combining results
• reranking.py: Cross-encoder reranking

API Layer (hindsight-api/hindsight_api/api/)

• http.py: FastAPI HTTP routers (~80KB) for all REST endpoints
• mcp.py: Model Context Protocol server implementation

Main operations:

• Retain: Store memories, extracts facts/entities/relationships
• Recall: Retrieve memories via 4 parallel strategies (semantic, BM25, graph, temporal) + reranking
• Reflect: Disposition-aware reasoning using memories and mental models.

Database

PostgreSQL with pgvector. Schema managed via Alembic migrations in hindsight-api/hindsight_api/alembic/. Migrations run automatically on API startup.

Key tables: banks, memory_units, documents, entities, entity_links

Adding Database Migrations

1. Create a new migration file in hindsight-api/hindsight_api/alembic/versions/:

   • File name format: <revision_id>_<description>.py (e.g., f1a2b3c4d5e6_add_new_index.py)
   • Use a unique hex revision ID (12 chars)
   • Set down_revision to the previous migration's revision ID

2. Migration template:

   """Description of the migration
   
   Revision ID: f1a2b3c4d5e6
   Revises: <previous_revision_id>
   Create Date: YYYY-MM-DD
   """
   from collections.abc import Sequence
   from alembic import context, op
   
   revision: str = "f1a2b3c4d5e6"
   down_revision: str | Sequence[str] | None = "<previous_revision_id>"
   branch_labels: str | Sequence[str] | None = None
   depends_on: str | Sequence[str] | None = None
   
   def _get_schema_prefix() -> str:
       """Get schema prefix for table names (required for multi-tenant support)."""
       schema = context.config.get_main_option("target_schema")
       return f'"{schema}".' if schema else ""
   
   def upgrade() -> None:
       schema = _get_schema_prefix()
       op.execute(f"CREATE INDEX ... ON {schema}table_name(...)")
   
   def downgrade() -> None:
       schema = _get_schema_prefix()
       op.execute(f"DROP INDEX IF EXISTS {schema}index_name")
   

3. Run migrations locally:

   # Set database URL and run migrations
   uv run hindsight-admin run-db-migration
   
   # Run on a specific tenant schema
   uv run hindsight-admin run-db-migration --schema tenant_xyz
   

Key Conventions

Code Quality

Always run the lint script after making Python or TypeScript/Node changes:

./scripts/hooks/lint.sh

This runs the same checks as the pre-commit hook (Ruff for Python, ESLint/Prettier for TypeScript).

Memory Banks

• Each bank is an isolated memory store (like a "brain" for one user/agent)
• Banks have dispositions (skepticism, literalism, empathy traits 1-5) affecting reflect
• Banks can have background context
• Bank isolation is strict - no cross-bank data leakage

API Design

• All endpoints operate on a single bank per request
• Multi-bank queries are client responsibility to orchestrate
• Disposition traits only affect reflect, not recall

Control Plane API Routes

When adding or modifying parameters in the dataplane API (hindsight-api), you must also update the control plane routes that proxy to it:

1. API Routes (hindsight-control-plane/src/app/api/):

   • recall/route.ts - proxies to /v1/default/banks/{bank_id}/memories/recall
   • reflect/route.ts - proxies to /v1/default/banks/{bank_id}/reflect
   • memories/retain/route.ts - proxies to /v1/default/banks/{bank_id}/memories/retain
   • Other routes follow the same pattern

2. Client types (hindsight-control-plane/src/lib/api.ts):

   • Update the TypeScript type definitions for recall(), reflect(), retain() etc.

3. Checklist when adding new API parameters:

   • Add parameter extraction in the route handler (destructure from body)
   • Pass the parameter to the SDK call
   • Update the client type definition in lib/api.ts
   • Update any UI components that need to use the new parameter

Python Style

• Python 3.11+, type hints required
• Async throughout (asyncpg, async FastAPI)
• Pydantic models for request/response
• Ruff for linting (line-length 120)
• No Python files at project root - maintain clean directory structure
• Never use multi-item tuple return values - prefer dataclass or Pydantic model for structured returns

Type Safety with Pydantic Models

NEVER use raw dict types for structured data. Always use Pydantic models:

• Use Pydantic BaseModel for all data structures passed between functions
• Add @field_validator for type coercion (e.g., ensuring datetimes are timezone-aware)
• Avoid dict.get() patterns - use typed model attributes instead
• Parse external data (JSON, API responses) into Pydantic models at the boundary
• This catches type errors at parse time, not deep in business logic

# BAD - error-prone dict access
def process(data: dict) -> str:
    return data.get("name", "")  # No validation, silent failures

# GOOD - typed and validated
class UserData(BaseModel):
    name: str
    created_at: datetime

    @field_validator("created_at", mode="before")
    @classmethod
    def ensure_tz_aware(cls, v):
        if isinstance(v, str):
            v = datetime.fromisoformat(v.replace("Z", "+00:00"))
        if v.tzinfo is None:
            return v.replace(tzinfo=timezone.utc)
        return v

def process(data: UserData) -> str:
    return data.name  # Type-safe, validated at construction

TypeScript Style

• Next.js App Router for control plane
• Tailwind CSS with shadcn/ui components

Adding New API Configuration Flags

When adding a new environment variable configuration:

1. config.py (hindsight-api/hindsight_api/config.py):

   • Add ENV_* constant for the environment variable name
   • Add DEFAULT_* constant for the default value
   • Add field to HindsightConfig dataclass
   • Add initialization in from_env() method

2. main.py (hindsight-api/hindsight_api/main.py):

   • Add field to the manual HindsightConfig() constructor call (search for "CLI override")

3. Use the config in code:

   from ...config import get_config
   config = get_config()
   value = config.your_new_field
   

4. Documentation (hindsight-docs/docs/developer/configuration.md):

   • Add to appropriate section table with Variable, Description, Default

Environment Setup

cp .env.example .env
# Edit .env with LLM API key

# Python deps
uv sync --directory hindsight-api/

# Node deps (uses npm workspaces)
npm install

Required env vars:

• HINDSIGHT_API_LLM_PROVIDER: openai, anthropic, gemini, groq, ollama, lmstudio
• HINDSIGHT_API_LLM_API_KEY: Your API key
• HINDSIGHT_API_LLM_MODEL: Model name (e.g., o3-mini, claude-sonnet-4-20250514)

Optional (uses local models by default):

• HINDSIGHT_API_EMBEDDINGS_PROVIDER: local (default) or tei
• HINDSIGHT_API_RERANKER_PROVIDER: local (default) or tei
• HINDSIGHT_API_DATABASE_URL: External PostgreSQL (uses embedded pg0 by default)