synthefy 5.0.0

Python client for the Synthefy API: time-series forecasting and Nori in-context tabular regression

Synthefy Python Client

Branch	Status
dev
main

A Python client for the Synthefy API. It provides time series forecasting (synchronous and asynchronous) and tabular in-context regression via SynthefyNoriClient — which runs against the hosted endpoint or fully locally — with an easy-to-use interface, full type hints, and pydantic validation.

Features

• Tabular In-Context Regression: SynthefyNoriClient predicts from labeled context rows in a single forward pass — hosted on Baseten or fully local, no training step
• Sync & Async Support: Separate clients for synchronous and asynchronous operations
• Professional Error Handling: Comprehensive exception hierarchy with detailed error messages
• Retry Logic: Built-in exponential backoff for transient errors (rate limits, server errors)
• Context Managers: Automatic resource cleanup with with and async with statements
• Pandas Integration: Built-in support for pandas DataFrames
• Type Safety: Full type hints and Pydantic validation

Installation

pip install synthefy

For optional fully-local tabular inference (no API key, runs in-process), install the extra:

pip install "synthefy[local]"

Quick Start

Basic Usage

from synthefy import SynthefyAPIClient, SynthefyAsyncAPIClient
import pandas as pd

# Synchronous client
with SynthefyAPIClient(api_key="your_api_key_here") as client:
    # Make requests...
    pass

# Asynchronous client
async with SynthefyAsyncAPIClient() as client:  # Uses SYNTHEFY_API_KEY env var
    # Make async requests...
    pass

Making a Forecast Request

from synthefy import SynthefyAPIClient
import pandas as pd
import numpy as np

# Create sample data with numeric metadata
history_data = {
    'date': pd.date_range('2024-01-01', periods=100, freq='D'),
    'sales': np.random.normal(100, 10, 100),
    'store_id': 1,
    'category_id': 101,
    'promotion_active': 0
}

target_data = {
    'date': pd.date_range('2024-04-11', periods=30, freq='D'),
    'sales': np.nan,  # Values to forecast
    'store_id': 1,
    'category_id': 101,
    'promotion_active': 1  # Promotion active in forecast period
}

history_df = pd.DataFrame(history_data)
target_df = pd.DataFrame(target_data)

# Synchronous forecast
with SynthefyAPIClient() as client:
    forecast_dfs = client.forecast_dfs(
        history_dfs=[history_df],
        target_dfs=[target_df],
        target_col='sales',
        timestamp_col='date',
        metadata_cols=['store_id', 'category_id', 'promotion_active'],
        leak_cols=[],
        model='sfm-moe-v1'
    )

# Result is a list of DataFrames with forecasts
forecast_df = forecast_dfs[0]
print(forecast_df[['timestamps', 'sales']].head())

Asynchronous Usage

import asyncio
from synthefy.api_client import SynthefyAsyncAPIClient

async def main():
    async with SynthefyAsyncAPIClient() as client:
        # Single async forecast
        forecast_dfs = await client.forecast_dfs(
            history_dfs=[history_df],
            target_dfs=[target_df],
            target_col='sales',
            timestamp_col='date',
            metadata_cols=['store_id', 'category_id', 'promotion_active'],
            leak_cols=[],
            model='sfm-moe-v1'
        )

        # Concurrent forecasts for multiple datasets
        tasks = []
        for i in range(3):
            # Create variations of your data
            modified_history = history_df.copy()
            modified_target = target_df.copy()
            modified_history['store_id'] = i + 1
            modified_target['store_id'] = i + 1

            task = client.forecast_dfs(
                history_dfs=[modified_history],
                target_dfs=[modified_target],
                target_col='sales',
                timestamp_col='date',
                metadata_cols=['store_id', 'category_id', 'promotion_active'],
                leak_cols=[],
                model='sfm-moe-v1'
            )
            tasks.append(task)

        # Execute all forecasts concurrently
        results = await asyncio.gather(*tasks)

        for i, forecast_dfs in enumerate(results):
            print(f"Forecast for store {i+1}: {len(forecast_dfs[0])} predictions")

# Run the async function
asyncio.run(main())

Backtesting

import asyncio
import pandas as pd
import numpy as np
from synthefy.data_models import ForecastV2Request
from synthefy.api_client import SynthefyAsyncAPIClient

async def main():

    # Create sample time series data
    dates = pd.date_range('2023-01-01', '2023-12-31', freq='D')
    data = {
        'date': dates,
        'sales': np.random.normal(100, 10, len(dates)),
        'store_id': 1,
        'category_id': 101,
        'promotion_active': np.random.choice([0, 1], len(dates), p=[0.7, 0.3])
    }
    df = pd.DataFrame(data)

    print(f"Created dataset with {len(df)} rows from {df['date'].min()} to {df['date'].max()}")

    # Use from_dfs_pre_split for backtesting with date-based windows
    request = ForecastV2Request.from_dfs_pre_split(
        dfs=[df],
        timestamp_col='date',
        target_cols=['sales'],
        model='sfm-moe-v1',
        cutoff_date='2023-06-01',  # Start backtesting from June 1st
        forecast_window='7D',      # 7-day forecast windows
        stride='14D',              # Move forward 14 days between windows
        metadata_cols=['store_id', 'category_id', 'promotion_active'],
        leak_cols=['promotion_active']  # Promotion data may leak into target
    )

    print(f"Created {len(request.samples)} forecast windows for backtesting")
    print("Window details:")
    for i, sample in enumerate(request.samples):
        history_start = sample[0].history_timestamps[0]
        history_end = sample[0].history_timestamps[-1]
        target_start = sample[0].target_timestamps[0]
        target_end = sample[0].target_timestamps[-1]
        print(f"  Window {i+1}: History {history_start} to {history_end}, Target {target_start} to {target_end}")

    # Make async forecast request
    async with SynthefyAsyncAPIClient() as client:
        response = await client.forecast(request)

        print(f"\nBacktesting completed with {len(response.samples)} forecast windows")

        # Process results for each window
        for i, sample in enumerate(response.samples):
            print(f"Window {i+1}: {len(sample.history_timestamps)} history points, "
                f"{len(sample.target_timestamps)} target points")

            # Access forecast values
            if hasattr(sample, 'forecast_values') and sample.forecast_values:
                print(f"  Forecast values: {sample.forecast_values[:3]}...")  # First 3 values
asyncio.run(main())

Advanced Configuration

from synthefy import SynthefyAPIClient
from synthefy.api_client import BadRequestError, RateLimitError

# Client with custom configuration
with SynthefyAPIClient(
    api_key="your_key",
    timeout=600.0,  # 10 minutes
    max_retries=3,
    organization="your_org_id",
    base_url="https://custom.synthefy.com"  # For enterprise customers
) as client:
    try:
        # Per-request configuration
        forecast_dfs = client.forecast_dfs(
            history_dfs=[history_df],
            target_dfs=[target_df],
            target_col='sales',
            timestamp_col='date',
            metadata_cols=['store_id'],
            leak_cols=[],
            model='sfm-moe-v1',
            timeout=120.0,  # Override client timeout for this request
            idempotency_key="unique-request-id",  # Prevent duplicate processing
            extra_headers={"X-Custom-Header": "value"}
        )
    except BadRequestError as e:
        print(f"Invalid request: {e}")
        print(f"Status code: {e.status_code}")
        print(f"Request ID: {e.request_id}")
    except RateLimitError as e:
        print(f"Rate limited: {e}")
        # Client automatically retries with exponential backoff
    except Exception as e:
        print(f"Unexpected error: {e}")

Nori — Tabular In-Context Regression

SynthefyNoriClient is a standalone client for Synthefy Nori, an in-context learning regressor. Each call supplies labeled context rows (X_train, y_train) and query rows (X_test); the model returns one predicted value per query row in a single forward pass — there is no training step.

It is independent of the forecasting client above (different model, different endpoint, different credential) but is exported from the same package. A single SynthefyNoriClient runs predictions either against the hosted endpoint or locally, selected with the mode argument ("remote" (default), "local", or "auto").

Use it from your AI coding assistant

Paste this into Claude Code, Cursor, or any AI coding assistant and it will wire Nori into your own project:

Look at my code/task/report here and figure out where Nori would best fit — it's
Synthefy's tabular foundation model for regression, used through the `synthefy`
client with no training loop and no hyperparameters. It runs fully on your own
machine (local mode, uses your GPU when one's available), or against the hosted
Synthefy API if you'd rather not run it locally.

1. Install it with this project's package manager, with the local extra
   (e.g. `uv add "synthefy[local]"`, or `pip install -U "synthefy[local]"`).

2. Use it wherever a tabular regression / prediction step fits:

   ```python
   from synthefy import SynthefyNoriClient

   # model is required -- name a size: "nori-30m" (~29.2M) or "nori-6m" (~6M base).
   client = SynthefyNoriClient(mode="local", model="nori-30m")   # runs on this machine, no API key

   y_pred = client.predict(
       X_train=X_train,   # lists, numpy arrays, or pandas — NaNs OK, imputed for you
       y_train=y_train,   # continuous target
       X_test=X_test,     # rows to score
   )                      # -> list of floats, one per X_test row (as_pandas=True for a Series)
   ```

X is a numeric feature matrix (or a pandas DataFrame — non-numeric columns are
encoded for you); y is a continuous target. If I already have a model, wire Nori
up alongside it on the same train/test split and metric so I can compare them. If
the best place to plug Nori in isn't obvious, show me where you'd put it and
confirm with me before making changes.

Prefer not to run it locally? Use the hosted API instead — create a key at
https://docs.synthefy.com/setup/api_key, then:
`client = SynthefyNoriClient(api_key="YOUR_API_KEY")` (or set SYNTHEFY_NORI_API_KEY).

Hosted Usage (mode="remote")

from synthefy import SynthefyNoriClient

# The key is sent as `Authorization: Bearer <key>` (gateway default).
# Pass it explicitly or set the SYNTHEFY_NORI_API_KEY environment variable.
client = SynthefyNoriClient(api_key="your_api_key")

predictions = client.predict(
    X_train=[[0.0, 1.0], [1.0, 0.0], [1.0, 1.0]],  # context features
    y_train=[1.0, 1.0, 2.0],                        # context targets
    X_test=[[2.0, 2.0], [0.5, 0.5]],                # query features
)
print(predictions)  # -> [<float>, <float>]  (one per X_test row)

X_train, y_train, and X_test accept Python lists, numpy arrays, or pandas objects (a DataFrame for the feature matrices; a Series or single-column DataFrame for y_train). When both X_train and X_test are DataFrames, non-numeric columns are encoded for you — fit on X_train and applied to X_test — so you can pass raw categorical columns directly:

import pandas as pd

X_train = pd.DataFrame({"price": [9.99, 4.50, 7.25], "region": ["NW", "SE", "NW"]})
y_train = pd.Series([120.0, 305.0, 180.0])
X_test  = pd.DataFrame({"region": ["SE"], "price": [5.00]})  # order need not match

predictions = client.predict(X_train, y_train, X_test)  # 'region' is encoded

By default each categorical column becomes a single column of ordinal codes (categories from X_train in sorted order — the model's own server-side convention): a value seen only in X_test maps to -1, and a missing value (NaN) stays NaN for server-side imputation. Pass categorical_encoding="onehot" for the previous one-hot behavior (indicator columns per category; missing values get their own indicator; unseen values map to an all-zeros group). Datetime columns and categorical columns with more than max_categorical_cardinality (default 100) distinct training values are dropped with a warning; timedelta columns are unsupported and raise (convert them to a number or string first). Numeric columns (including bool) pass through unchanged, with NaN imputed server-side. Any object-dtype column is treated as categorical (including numeric-looking strings such as IDs or zip codes, and object date values) — cast genuine numeric columns to a numeric dtype if you want them kept as magnitudes. (Plain lists/numpy arrays must already be numeric — encoding needs column names.)

Shapes are validated client-side: X_train and y_train must have the same number of rows, and X_test must have the same number of features as X_train. When both X_train and X_test are DataFrames, X_test is aligned to X_train's columns by name (so column order is irrelevant), and a mismatch in the column sets raises. Missing values (NaN) are allowed — you don't need to fill them in beforehand; the model imputes them server-side.

predict returns a plain list[float] by default. Pass as_pandas=True to get a pandas Series instead — one value per X_test row, named after y_train and indexed by X_test's index (when X_test is a DataFrame), so predictions join straight back:

preds = client.predict(X_train, y_train, X_test, as_pandas=True)
# preds is a pd.Series named after y_train, sharing X_test's index

By default the client targets the Baseten inference gateway (https://inference.baseten.co/predict); model= is required and names a size — "nori-30m" (→ synthefy/nori-30m) or "nori-6m" (→ synthefy/nori-6m). To target a dedicated deployment instead, point base_url/endpoint at it and set model=None (the dedicated endpoint takes the body verbatim, with no model field):

from synthefy.nori_client import DEDICATED_BASE_URL, DEDICATED_ENDPOINT

client = SynthefyNoriClient(
    api_key="your_api_key",
    base_url=DEDICATED_BASE_URL,    # https://model-3m5j7y9w.api.baseten.co
    endpoint=DEDICATED_ENDPOINT,    # /environments/production/predict
    model=None,
    auth_scheme="Api-Key",          # dedicated endpoints use Api-Key, not Bearer
)

timeout and max_retries are also configurable on the constructor.

Authentication

• The only credential is your Synthefy Nori API key, created in the Synthefy Console. It authenticates against the Baseten-hosted gateway, but you do not need a Baseten account.
• Provide it via the api_key argument or the SYNTHEFY_NORI_API_KEY environment variable. It is sent as the header Authorization: <auth_scheme> <key>. The scheme defaults to Bearer (required by the gateway); pass auth_scheme="Api-Key" for a dedicated deployment.

Errors

The Nori client reuses the package's exception hierarchy:

• HTTP 400 → BadRequestError, carrying the server's error string as the message (e.g. a missing field or unsupported task).
• HTTP 401 → AuthenticationError (bad or missing key).
• Transient errors (timeouts, connection errors, 429, 5xx) are retried with exponential backoff, then surface as RateLimitError / InternalServerError / APITimeoutError / APIConnectionError.

Local Usage (mode="local", Optional, No Network)

The same prediction can run locally — no network call and no API key — via the optional synthefy-nori package. Install the extra:

pip install "synthefy[local]"

The local extra (via synthefy-nori>=0.10.0, which provides the model= size selector) supports Python >= 3.9, the same floor as the base package.

from synthefy import SynthefyNoriClient

client = SynthefyNoriClient(mode="local")  # no API key needed
predictions = client.predict(
    X_train=[[0.0, 1.0], [1.0, 0.0], [1.0, 1.0]],
    y_train=[1.0, 1.0, 2.0],
    X_test=[[2.0, 2.0]],
)

predict has the same signature in every mode. The synthefy-nori dependency is imported lazily on first use; if it is not installed, a clear ImportError is raised telling you to pip install "synthefy[local]".

Use mode="auto" to prefer local when synthefy-nori is installed and transparently fall back to the hosted endpoint (which then requires an API key) otherwise:

client = SynthefyNoriClient(api_key="your_api_key", mode="auto")
print(client.mode)  # "local" if synthefy-nori is installed, else "remote"

Categorical / Ordinal Targets (discretize= / categorical_levels=)

When the target only takes a small set of discrete values (a 1–5 rating, a count, a quality score), pass discretize= and every returned prediction is one of the target's own levels instead of a continuous estimate:

labels = client.predict(X_train, y_train, X_test, discretize="snap-mean")
labels = client.predict(
    X_train, y_train, X_test,
    discretize="snap-mean",
    categorical_levels=[1, 2, 3, 4, 5],   # the full scale, if the context may under-cover it
)

Discretization is strictly opt-in — nothing is snapped unless you ask. categorical_levels is the set of values the target can take (numeric; order and duplicates don't matter); it defaults to the distinct values of y_train, which is leak-safe. A NaN prediction stays NaN rather than becoming a confident label.

Capability differs by mode:

• Remote: the hosted endpoint returns point predictions (the distribution mean), so the supported strategy is discretize="snap-mean" — the nearest level to the point prediction, computed client-side and identical to local "snap-mean". Other strategies raise a ValueError pointing here.
• Local (pip install "synthefy[local]", with a synthefy-nori recent enough to ship synthefy_nori.discretize): the full strategy set is forwarded — "map-cell" (accuracy-optimal), "median-cell" (MAE-optimal), "snap-mean" (QWK), "snap-median", "expected-level", "prior-match". Choose by the metric you are scored on; see the synthefy-nori docs. An older synthefy-nori raises an ImportError with an upgrade hint.

If your task is scored by squared error / R², don't discretize — the continuous mean is already optimal for those metrics.

API Reference

SynthefyNoriClient (Tabular Regression)

• SynthefyNoriClient(api_key=None, *, mode="remote", timeout=300.0, max_retries=2, base_url=..., endpoint=..., model, user_agent=None) — model is required ("nori-6m" / "nori-30m"; None for a dedicated endpoint)
  • mode: "remote" (hosted, default), "local" (in-process via synthefy-nori), or "auto" (local if installed, else remote).
  • api_key (remote mode) falls back to the SYNTHEFY_NORI_API_KEY environment variable. Not required in local mode.
  • For a dedicated deployment, pass base_url/endpoint and model=None.
• predict(X_train, y_train, X_test, task="regression", *, timeout=None, extra_headers=None) -> List[float]
  • Returns one predicted value per row of X_test. timeout/extra_headers apply to remote mode only.
  • Inputs accept Python lists, numpy arrays, or pandas DataFrames/Series. Feature columns must be numeric; DataFrame X_test is aligned to X_train by column name; non-numeric columns are encoded (fit on X_train; categorical_encoding="ordinal" by default, "onehot" available); missing values (NaN) are imputed server-side.
  • max_categorical_cardinality (default 100): non-numeric columns with more distinct training values than this — and datetime columns — are dropped with a warning instead of encoded.
  • as_pandas=True returns a pandas Series (named after y_train, indexed by X_test) instead of the default list[float].
  • discretize= / categorical_levels= map predictions onto a discrete target's levels (see Categorical / Ordinal Targets); remote mode supports discretize="snap-mean", local mode the full strategy set of the installed synthefy-nori.
• mode: the resolved mode ("auto" becomes "local"/"remote" at construction).
• close() / context manager support (with SynthefyNoriClient(...) as client:).

SynthefyAPIClient (Synchronous)

The synchronous client class for interacting with the Synthefy API.

Constructor Parameters

• api_key: Your Synthefy API key (can also be set via SYNTHEFY_API_KEY environment variable)
• timeout: Request timeout in seconds (default: 300.0 / 5 minutes)
• max_retries: Number of retries for transient errors (default: 2)
• base_url: API base URL (default: "https://forecast.synthefy.com")
• organization: Optional organization ID for multi-tenant setups
• user_agent: Custom user agent string

Methods

• forecast(request, *, timeout=None, idempotency_key=None, extra_headers=None) -> ForecastV2Response
  • Make a direct forecast request with a ForecastV2Request object
• forecast_dfs(history_dfs, target_dfs, target_col, timestamp_col, metadata_cols, leak_cols, model) -> List[pd.DataFrame]
  • Convenience method for working directly with pandas DataFrames
• close(): Manually close the HTTP client
• Context manager support: Use with with SynthefyAPIClient() as client:

SynthefyAsyncAPIClient (Asynchronous)

The asynchronous client class for non-blocking operations and concurrent requests.

Constructor Parameters

Same as SynthefyAPIClient.

Methods

• async forecast(request, *, timeout=None, idempotency_key=None, extra_headers=None) -> ForecastV2Response
  • Async version of forecast method
• async forecast_dfs(history_dfs, target_dfs, target_col, timestamp_col, metadata_cols, leak_cols, model) -> List[pd.DataFrame]
  • Async version of forecast_dfs method
• async aclose(): Manually close the async HTTP client
• Async context manager support: Use with async with SynthefyAsyncAPIClient() as client:

Exception Hierarchy

All exceptions inherit from SynthefyError:

• APITimeoutError: Request timed out
• APIConnectionError: Network/connection issues
• APIStatusError: Base class for HTTP status errors
  • BadRequestError (400, 422): Invalid request data
  • AuthenticationError (401): Invalid API key
  • PermissionDeniedError (403): Access denied
  • NotFoundError (404): Resource not found
  • RateLimitError (429): Rate limit exceeded
  • InternalServerError (5xx): Server errors

Each status error includes:

• status_code: HTTP status code
• request_id: Request ID for debugging (if available)
• error_code: API-specific error code (if available)
• response_body: Raw response body

Configuration

Environment Variables

• SYNTHEFY_API_KEY: Your Synthefy API key (forecasting client)
• SYNTHEFY_NORI_API_KEY: Your hosted-Nori API key (SynthefyNoriClient)

Support

For support and questions:

• Email: [e-mail]

License

MIT License - see LICENSE file for details.