fleet-memory/hindsight-integrations/pydantic-ai/hindsight_pydantic_ai/tools.py
Ben cab5a40f3a
feat: add Pydantic AI integration for persistent agent memory (#441)
* feat: add Pydantic AI integration for persistent agent memory

Adds hindsight-pydantic-ai package providing Hindsight-backed memory
tools for Pydantic AI agents. Since Pydantic AI is async-native, tools
use the hindsight-client async API directly (no thread-pool compat layer).

- create_hindsight_tools(): factory returning retain/recall/reflect Tool instances
- memory_instructions(): auto-injects relevant memories via Agent instructions
- Global configure()/get_config()/reset_config() following existing integration pattern

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* doc: add README for Pydantic AI integration

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>
2026-03-02 15:14:00 +01:00

243 lines
8.9 KiB
Python

"""Pydantic AI tools for Hindsight memory operations.
Provides factory functions that create Pydantic AI ``Tool`` instances
backed by Hindsight's retain/recall/reflect APIs.
"""
from __future__ import annotations
import logging
from collections.abc import Awaitable, Callable
from typing import Any
from hindsight_client import Hindsight
from pydantic_ai import RunContext, Tool
from .config import get_config
from .errors import HindsightError
logger = logging.getLogger(__name__)
def _resolve_client(
client: Hindsight | None,
hindsight_api_url: str | None,
api_key: str | None,
) -> Hindsight:
"""Resolve a Hindsight client from explicit args or global config."""
if client is not None:
return client
config = get_config()
url = hindsight_api_url or (config.hindsight_api_url if config else None)
key = api_key or (config.api_key if config else None)
if url is None:
raise HindsightError(
"No Hindsight API URL configured. "
"Pass client= or hindsight_api_url=, or call configure() first."
)
kwargs: dict[str, Any] = {"base_url": url, "timeout": 30.0}
if key:
kwargs["api_key"] = key
return Hindsight(**kwargs)
def create_hindsight_tools(
*,
bank_id: str,
client: Hindsight | None = None,
hindsight_api_url: str | None = None,
api_key: str | None = None,
budget: str = "mid",
max_tokens: int = 4096,
tags: list[str] | None = None,
recall_tags: list[str] | None = None,
recall_tags_match: str = "any",
include_retain: bool = True,
include_recall: bool = True,
include_reflect: bool = True,
) -> list[Tool]:
"""Create Hindsight memory tools for a Pydantic AI agent.
Returns a list of ``Tool`` instances that can be passed directly to
``Agent(tools=...)``. Each tool is an async closure that captures
the Hindsight client — no ``RunContext`` or deps modification needed.
Args:
bank_id: The Hindsight memory bank to operate on.
client: Pre-configured Hindsight client (preferred).
hindsight_api_url: API URL (used if no client provided).
api_key: API key (used if no client provided).
budget: Recall/reflect budget level (low/mid/high).
max_tokens: Maximum tokens for recall results.
tags: Tags applied when storing memories via retain.
recall_tags: Tags to filter when searching memories.
recall_tags_match: Tag matching mode (any/all/any_strict/all_strict).
include_retain: Include the retain (store) tool.
include_recall: Include the recall (search) tool.
include_reflect: Include the reflect (synthesize) tool.
Returns:
List of Pydantic AI Tool instances.
Raises:
HindsightError: If no client or API URL can be resolved.
"""
resolved_client = _resolve_client(client, hindsight_api_url, api_key)
# Resolve defaults from global config
config = get_config()
effective_tags = tags if tags is not None else (config.tags if config else None)
effective_recall_tags = (
recall_tags if recall_tags is not None else (config.recall_tags if config else None)
)
effective_recall_tags_match = recall_tags_match or (config.recall_tags_match if config else "any")
effective_budget = budget or (config.budget if config else "mid")
effective_max_tokens = max_tokens or (config.max_tokens if config else 4096)
tools: list[Tool] = []
if include_retain:
async def hindsight_retain(content: str) -> str:
"""Store information to long-term memory for later retrieval.
Use this to save important facts, user preferences, decisions,
or any information that should be remembered across conversations.
"""
try:
retain_kwargs: dict[str, Any] = {"bank_id": bank_id, "content": content}
if effective_tags:
retain_kwargs["tags"] = effective_tags
await resolved_client.aretain(**retain_kwargs)
return "Memory stored successfully."
except Exception as e:
logger.error(f"Retain failed: {e}")
raise HindsightError(f"Retain failed: {e}") from e
tools.append(Tool(hindsight_retain, takes_ctx=False))
if include_recall:
async def hindsight_recall(query: str) -> str:
"""Search long-term memory for relevant information.
Use this to find previously stored facts, preferences, or context.
Returns a numbered list of matching memories.
"""
try:
recall_kwargs: dict[str, Any] = {
"bank_id": bank_id,
"query": query,
"budget": effective_budget,
"max_tokens": effective_max_tokens,
}
if effective_recall_tags:
recall_kwargs["tags"] = effective_recall_tags
recall_kwargs["tags_match"] = effective_recall_tags_match
response = await resolved_client.arecall(**recall_kwargs)
if not response.results:
return "No relevant memories found."
lines = []
for i, result in enumerate(response.results, 1):
lines.append(f"{i}. {result.text}")
return "\n".join(lines)
except Exception as e:
logger.error(f"Recall failed: {e}")
raise HindsightError(f"Recall failed: {e}") from e
tools.append(Tool(hindsight_recall, takes_ctx=False))
if include_reflect:
async def hindsight_reflect(query: str) -> str:
"""Synthesize a thoughtful answer from long-term memories.
Use this when you need a coherent summary or reasoned response
about what you know, rather than raw memory facts.
"""
try:
reflect_kwargs: dict[str, Any] = {
"bank_id": bank_id,
"query": query,
"budget": effective_budget,
}
response = await resolved_client.areflect(**reflect_kwargs)
return response.text or "No relevant memories found."
except Exception as e:
logger.error(f"Reflect failed: {e}")
raise HindsightError(f"Reflect failed: {e}") from e
tools.append(Tool(hindsight_reflect, takes_ctx=False))
return tools
def memory_instructions(
*,
bank_id: str,
client: Hindsight | None = None,
hindsight_api_url: str | None = None,
api_key: str | None = None,
query: str = "relevant context about the user",
budget: str = "low",
max_results: int = 5,
max_tokens: int = 4096,
prefix: str = "Relevant memories:\n",
tags: list[str] | None = None,
tags_match: str = "any",
) -> Callable[[RunContext[Any]], Awaitable[str]]:
"""Create an instructions function that auto-injects relevant memories.
Returns an async callable suitable for use with Pydantic AI's
``instructions`` parameter. Because instructions are re-evaluated
on every run, memories stay fresh even when ``message_history``
is reused.
Args:
bank_id: The Hindsight memory bank to recall from.
client: Pre-configured Hindsight client (preferred).
hindsight_api_url: API URL (used if no client provided).
api_key: API key (used if no client provided).
query: The recall query to find relevant memories.
budget: Recall budget level (low/mid/high).
max_results: Maximum number of memories to include.
max_tokens: Maximum tokens for recall results.
prefix: Text prepended before the memory list.
tags: Tags to filter recall results.
tags_match: Tag matching mode (any/all/any_strict/all_strict).
Returns:
An async function compatible with ``Agent(instructions=[...])``.
Raises:
HindsightError: If no client or API URL can be resolved.
"""
resolved_client = _resolve_client(client, hindsight_api_url, api_key)
async def _instructions(ctx: RunContext[Any]) -> str:
try:
recall_kwargs: dict[str, Any] = {
"bank_id": bank_id,
"query": query,
"budget": budget,
"max_tokens": max_tokens,
}
if tags:
recall_kwargs["tags"] = tags
recall_kwargs["tags_match"] = tags_match
response = await resolved_client.arecall(**recall_kwargs)
results = response.results[:max_results] if response.results else []
if not results:
return ""
lines = [prefix]
for i, result in enumerate(results, 1):
lines.append(f"{i}. {result.text}")
return "\n".join(lines)
except Exception:
# Silently return empty — instructions failures shouldn't block the agent
return ""
return _instructions