Python Library

The Neuronpedia Python library makes it easy to use the API from Python.

pip install neuronpedia

Source code: webapp-python-client on GitHub

Set Your API Key

Some calls need an API key, for example calls that upload data or change your account.

1. Sign in at neuronpedia.org.
2. Copy your API key from neuronpedia.org/account.
3. Set the environment variable NEURONPEDIA_API_KEY, for example in a .env file.

from dotenv import load_dotenv

load_dotenv()  # loads NEURONPEDIA_API_KEY from .env

Example - Get a Feature

from neuronpedia.np_sae_feature import SAEFeature

sae_feature = SAEFeature.get("gemma-2-2b", "20-gemmascope-res-16k", "10956")
print(sae_feature)

Example - Upload a Vector, Then Steer With It

from neuronpedia.np_vector import NPVector
from neuronpedia.sample_data import GEMMA2_2B_IT_DINOSAURS_VECTOR

np_vector = NPVector.new(
    label="dinosaurs",
    model_id="gemma-2-2b-it",
    layer_num=20,
    hook_type="hook_resid_pre",
    vector=GEMMA2_2B_IT_DINOSAURS_VECTOR,
    default_steer_strength=44,
)

response = np_vector.steer_chat(
    steered_chat_messages=[{"role": "user", "content": "Write a one sentence story."}]
)
print("UI Steering at: " + response["shareUrl"])

Example Notebooks

Notebook	What it does
get_sae_feature	Get a feature and its data.
steer_completion	Steer a completion with a vector.
upload_vector_and_activations	Upload a vector, test it, and upload its activations.
upload_features	Upload your own features. See Upload Your SAEs.
new-model	Add a new model.
generate_graph	Make an attribution graph.
upload_graph	Upload an attribution graph. See Upload Graphs.
llama_3.3_70b_instruct	Get activations and top features for your text, with Goodfire's Llama 3.3 70B SAE.

Other Libraries

These libraries work with Neuronpedia:

• SAELens - Train and load SAEs. Many SAEs on Neuronpedia can be loaded with SAELens.
• circuit-tracer - Make attribution graphs on your own GPU, then upload them to Neuronpedia.
• interp-engine - The library that Neuronpedia uses to run models. See interp-engine.