lethe-memory
Python bindings to the Rust core of lethe, a self-improving memory store for LLM agents. Built with PyO3 + maturin, distributed as wheels.
Install
pip install lethe-memory
Use
from lethe_memory import MemoryStore
store = MemoryStore("./my_memories") # encoders default to MiniLM
store.add("I prefer window seats on flights", session_id="trip")
store.add("My wife needs aisle seats", session_id="trip")
store.add("I work at Google as a software engineer", session_id="work")
for hit in store.retrieve("What are my travel preferences?", k=5):
print(f" [{hit.score:.1f}] {hit.content}")
store.save()
The wheel ships the Rust lethe-core retrieval pipeline (BM25 + dense
hybrid, cross-encoder rerank, clustered RIF), the same code path the CLI
uses, exposed via PyO3 with Python::allow_threads around all native
work so multi-threaded Python callers see real parallelism.
Constructor knobs
MemoryStore(
path,
bi_encoder="Xenova/all-MiniLM-L6-v2",
cross_encoder="Xenova/ms-marco-MiniLM-L-6-v2",
rif_config=None, # RIFConfig(n_clusters=30, ...)
k_shallow=30,
k_deep=100,
confidence_threshold=4.0,
dedup_threshold=0.95,
)
See also
- Project landing page: architecture, benchmarks, research journey
lethe-cli(Homebrew:lethe): the standalone CLI
License: MIT.
1 maintainer
Release files for lethe-memory 0.17.0
For a detailed explanation of source distributions (sdists) and built distributions (wheels), please see the package formats documentation.
Built distributions (wheels)
| File | Interpreter | ABI | Platform | Reset |
|---|---|---|---|---|
| lethe_memory-0.17.0-cp39-abi3-win_arm64.whl | CPython 3.9 | abi3 | Windows ARM64 | Details |
| lethe_memory-0.17.0-cp39-abi3-win_amd64.whl | CPython 3.9 | abi3 | Windows x86-64 | Details |
| lethe_memory-0.17.0-cp39-abi3-macosx_11_0_arm64.whl | CPython 3.9 | abi3 | macOS 11.0+ ARM64 | Details |
Total release size: 90.6 MB
Release files / lethe_memory-0.17.0-cp39-abi3-win_arm64.whl
| Download URL | lethe_memory-0.17.0-cp39-abi3-win_arm64.whl |
|---|---|
| Size | 23.2 MB |
| Tags | CPython 3.9 Windows ARM64 abi3 |
|
SHA-256 checksum How to use checksums |
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|
|
BLAKE2b-256 checksum How to use checksums |
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Yes |
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twine/6.1.0 CPython/3.13.12
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Transparency logRelease files / lethe_memory-0.17.0-cp39-abi3-win_amd64.whl
| Download URL | lethe_memory-0.17.0-cp39-abi3-win_amd64.whl |
|---|---|
| Size | 23.1 MB |
| Tags | CPython 3.9 Windows x86-64 abi3 |
|
SHA-256 checksum How to use checksums |
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Yes |
| Uploaded via |
twine/6.1.0 CPython/3.13.12
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Transparency logRelease files / lethe_memory-0.17.0-cp39-abi3-macosx_11_0_arm64.whl
| Download URL | lethe_memory-0.17.0-cp39-abi3-macosx_11_0_arm64.whl |
|---|---|
| Size | 44.3 MB |
| Tags | CPython 3.9 abi3 macOS 11.0+ ARM64 |
|
SHA-256 checksum How to use checksums |
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cdc5eb987c030d0c01da274752747b0f77355cc20999417408db12c29b26cb22
|
| Upload date | |
|
Uploaded using Trusted Publishing? What is trusted publishing? |
Yes |
| Uploaded via |
twine/6.1.0 CPython/3.13.12
|
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