proxyml

Python SDK for the ProxyML API.

Why ProxyML?

Most explainability tools require sending your data to a third-party server. ProxyML never sees your training data. You generate synthetic data locally, score it with your own model, and only the surrogate model and summary statistics are uploaded — your data stays yours.

Installation

pip install proxyml

Want to train a challenger model locally, with no round-trip to the API? Install the local extra (adds scikit-learn and scipy):

pip install 'proxyml[local]'

Setup

ProxyML requires an API key. Set it as an environment variable before importing the package:

export PROXYML_API_KEY="your-api-key"

Optionally override the base URL (defaults to https://api.proxyml.ai/api/v1):

export PROXYML_BASE_URL="https://api.proxyml.ai/api/v1"

Quick Start

import pandas as pd
import proxyml
from proxyml import get_schema

# 1. Load your dataset and generate a schema
df = pd.read_csv("data.csv")
schema = get_schema(df, immutable_cols=["age", "gender"])

# 2. Upload the schema under a name — synthesis and training reference it by name
SCHEMA_NAME = "my_schema"
proxyml.put_schema(schema, name=SCHEMA_NAME)

# 3. Generate synthetic training data
synth_df = proxyml.synthesize_data(num_points=500, schema_name=SCHEMA_NAME)

# 4. Score synthetic data with your black-box model
predictions = my_model.predict(synth_df.values.tolist())

# 5. Train a surrogate model
proxyml.train_surrogate(
    samples=synth_df.values.tolist(),
    predictions=predictions,
    feature_names=list(synth_df.columns),
    schema_name=SCHEMA_NAME,
)

# 6. Find a counterfactual explanation
sample = df.iloc[0].tolist()
cf = proxyml.find_counterfactual(sample=sample, target=1, version=None)

if cf is not None:
    original = synth_df.iloc[0].to_dict()
    cf_dict = cf.iloc[0].to_dict()
    current_pred = my_model.predict([sample])[0]
    cf_pred = my_model.predict([cf.values.tolist()[0]])[0]

    explanation = proxyml.interpret_counterfactual(
        sample=original,
        counterfactual=cf_dict,
        prediction_changed=(current_pred != cf_pred),
    )
    print(explanation)

See docs/quickstart.md for a full walkthrough and docs/api.md for complete API reference.

Core Concepts

Surrogate model — A fast, interpretable model trained to approximate your black-box model's behavior on synthetic data. Once trained, it can be queried directly via the ProxyML API.

Challenger model — Trained the same way as a surrogate, but locally (proxyml.local, no round-trip to the API) and against either real ground-truth labels (a genuine challenger to compare against a champion model) or a black box's predictions (a surrogate/explainer). Its export is structurally identical to a server-trained surrogate's, so the two can be compared and scored with the exact same arithmetic.

Counterfactual explanation — Given a prediction, a counterfactual is the minimal change to input features that would produce a different prediction. It answers: "What would have to be different for the outcome to change?"

Schema — Describes the statistical properties of each feature (type, range, distribution). Used to generate realistic synthetic data and constrain counterfactual search.

API Reference

Full documentation: docs/api.md

Examples

• examples/basic_usage.py — Schema upload, data synthesis, surrogate training
• examples/counterfactual_example.py — Counterfactual search and interpretation
• examples/regression_example.py — Regression with immutable features
• examples/multiclass_example.py — Multi-class classification with per-class feature importances
• examples/testing_example.py — Using a surrogate as a reference model in CI
• examples/surrogate_export_example.py — Exporting a surrogate and reproducing its predictions locally

License

Apache 2.0 — see LICENSE.