mostlyright

The public-data SDK for quants, ML pipelines, and AI agents.

mostlyright is a Python + TypeScript SDK for quants, ML engineers, and AI agents — one direct, schema-versioned interface to every public data source that matters. Today's adapters ship weather data (live METAR/ASOS, forecasts, GHCNh climate history, NWS CLI text products) and prediction-market settlements (Kalshi NHIGH/NLOW, Polymarket discovery + settlement, Kalshi + Polymarket trades). Next: SEC filings (EDGAR), equities structured data, Federal Reserve series (FRED), court filings, FDA approvals — anywhere the data is public, we ship the adapter. Local-first: no hosted backend, no API key for the public-data layer, byte-equivalent reproducibility from research to backtest, and leakage-free training pairs for ML pipelines.

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Install

# Python
pip install 'mostlyrightmd[research]'

# TypeScript / Node
pnpm add mostlyright

Python 3.11+. Node 18+. No API key required for any package below.

Quickstart

# Python
import mostlyright

df = mostlyright.research("KNYC", "2025-01-06", "2025-01-12")
print(df.head())
# pandas DataFrame: one row per LST settlement date
# Columns: date, station, cli_high_f, cli_low_f, obs_high_f, obs_low_f,
#          obs_mean_f, obs_count, fcst_*, market_close_utc

// TypeScript
import { research } from "mostlyright";

const rows = await research("KNYC", "2025-01-06", "2025-01-12");
console.log(rows[0]);
// ReadonlyArray<PairsRow>: same schema as Python, JSON-serializable

First call writes a parquet (Python) or JSON-envelope (Node) cache to ~/.mostlyright/cache/. Subsequent calls in the same window are local-only — no network.

Full quickstart with concepts at https://mostlyright.md/docs/sdk/.

Packages

Python (PyPI)

Package	Description	Downloads	Status
mostlyrightmd	Core types, schemas, validators, the research() join, and snapshot primitives. Imports as mostlyright.		stable
mostlyrightmd-weather	Weather data fetchers — live METAR (AWC), ASOS archive (IEM), historical observations (GHCNh), and NWS climate text products (CLI). Direct public-API access.		stable
mostlyrightmd-markets	Prediction-market data — Kalshi NHIGH/NLOW weather-contract resolvers, Polymarket discovery + settlement, and Kalshi + Polymarket trade history.		stable
mostlyrightmd-edgar	SEC filings (10-K, 10-Q, 8-K) — direct EDGAR full-text + facts access.	n/a	planned
mostlyrightmd-equities	Equities structured data — fundamentals, corporate actions, normalized XBRL pulls.	n/a	planned
mostlyrightmd-fred	Federal Reserve economic data (FRED series, observations, releases).	n/a	planned
mostlyrightmd-courts	Court filings — federal (PACER) and state dockets, opinions, party data.	n/a	planned
mostlyrightmd-fda	FDA approvals — drug + medical-device clearance records, post-market events.	n/a	planned

TypeScript (npm)

Package	Description	Downloads	Status
mostlyright	Meta package — one import { research } from "mostlyright" for weather data + prediction-market settlements + the core join.		stable
@mostlyrightmd/core	Core types, schemas, validators, temporal-safety primitives, and the research() join.		stable
@mostlyrightmd/weather	Weather data fetchers — live METAR (AWC), ASOS archive (IEM), historical observations (GHCNh), and NWS climate text products (CLI).		stable
@mostlyrightmd/markets	Prediction-market data — Kalshi NHIGH/NLOW weather-contract resolvers, Polymarket discovery + settlement, and Kalshi + Polymarket trade history.		stable
@mostlyrightmd/edgar	SEC filings (10-K, 10-Q, 8-K) — direct EDGAR full-text + facts access.	n/a	planned
@mostlyrightmd/equities	Equities structured data — fundamentals, corporate actions, normalized XBRL pulls.	n/a	planned
@mostlyrightmd/fred	Federal Reserve economic data (FRED series, observations, releases).	n/a	planned
@mostlyrightmd/courts	Court filings — federal (PACER) and state dockets, opinions, party data.	n/a	planned
@mostlyrightmd/fda	FDA approvals — drug + medical-device clearance records, post-market events.	n/a	planned

What you can build

Backtest prediction-market settlements

Pull joined climate + observation rows for a settlement window, compare against contract spec, and produce a deterministic settlement decision.

import mostlyright
from mostlyright.markets.catalog import kalshi_nhigh

# 1. What does the contract settle on?
contract = kalshi_nhigh.resolve("KHIGHNYC", date(2025, 1, 15))
# 2. Pull the data that decides it.
df = mostlyright.research(contract.settlement_station, "2025-01-15", "2025-01-15")
# 3. Apply the threshold and decide.

Train models with train/infer source parity

research() stamps a source identity on every row. The validator catches train/infer mismatches at load time, instead of silently corrupting predictions in production.

from mostlyright.mode2 import research_by_source
from mostlyright.core import validate_dataframe

train = research_by_source("KNYC", "iem.archive", "2024-01-01", "2024-12-31")
# Validator pins the schema's expected source. SourceMismatchError fires if
# you accidentally route a Mode 1 (fused AWC+IEM+GHCNh) DataFrame through a
# Mode 2 (iem.archive only) schema.
validate_dataframe(train, schema_id="schema.observation.v1")

Feed AI agents structured public data

Every response carries a stable schema.*.v1 URI and serializes to JSON-Schema-validated shapes. Drop responses into MCP tool outputs or OpenAI/Anthropic function-call returns without re-shaping.

import { research } from "mostlyright";
import { validateRows } from "@mostlyrightmd/core/validator";

const rows = await research("KNYC", "2025-01-06", "2025-01-12");
const result = validateRows(rows, "schema.observation.v1");
// result.audit_log carries the schema URI + source identity + row count
// — ready to pass through to an agent's tool-call response.

Why mostlyright

• No hosted backend. Direct calls to public APIs (NOAA, NWS, IEM, Kalshi, Polymarket). No proxy. No vendor account. No rate-limited tier.
• Local-first cache. Parquet (Python) or JSON envelope (Node) at ~/.mostlyright/cache/. Byte-stable across runs — deterministic backtests.
• Schema-versioned outputs. Every response carries a stable schema.*.v1 URI. Train/infer source mismatches fail loudly instead of silently corrupting models.
• Python + TypeScript peers. Same research() shape, byte-equivalent on the parity fixtures. Use whichever runtime your stack prefers.
• MIT licensed. Use it commercially. Fork it. Ship it.

Documentation

• Quickstart + concepts: https://mostlyright.md/docs/sdk/
• API reference: https://mostlyright.md/docs/sdk/ (Python + TypeScript reference auto-generated per release)
• Migration from the legacy hosted-API client: https://mostlyright.md/docs/sdk/migration/legacy/

Contributing

Bug reports, feature requests, and pull requests are welcome. See CONTRIBUTING.md for the development workflow (fork → branch → PR) and the test gate. See CODE_OF_CONDUCT.md for community guidelines.

For security issues, see SECURITY.md — do not file public issues for vulnerabilities; email vu@mostlyright.md instead.

License

MIT. See LICENSE.

Acknowledgements

mostlyright calls the following public APIs directly. We are grateful for the work that makes weather and market data accessible at the public-API layer:

• NOAA Aviation Weather Center (AWC) — live METAR feeds
• Iowa State University Iowa Environmental Mesonet (IEM) — ASOS archive + CLI text products
• NOAA National Centers for Environmental Information (NCEI) — GHCNh historical observations
• National Weather Service (NWS) — climate data products (CLI) and forecast model outputs
• Open-Meteo — multi-provider forecast aggregation (added Phase 20). 36 models across NCEP / ECMWF / DWD / Météo-France / Asia / Oceania / Europe / GEM Canada. Leakage-safe via per-cycle endpoint + conservative issued_at lower bound. See docs/forecast-sources.md.
• Kalshi + Polymarket — public prediction-market metadata + settlement feeds