Packages & versioning

Mostly Right ships publicly for Python and TypeScript. One meta-package installs all common methods; per-domain packages let you depend on only what you use.

Install everything

pip install mostlyrightmd

pnpm add mostlyright

The Python import name is mostlyright. Support floors are Python 3.11+ and Node 20+.

Packages

Domain	Python	TypeScript
Core / meta	mostlyrightmd	mostlyright / @mostlyrightmd/core
Weather	mostlyrightmd-weather	@mostlyrightmd/weather
Markets	mostlyrightmd-markets	@mostlyrightmd/markets
Economy	mostlyrightmd-economy	@mostlyrightmd/economy
Finance	mostlyrightmd-finance	@mostlyrightmd/finance

All packages share the mostlyright namespace and follow the same schema and source-identity conventions. Inspect each runtime’s returned schema before freezing a cross-runtime model contract.

Python package name

Install mostlyrightmd from PyPI. The older package named mostlyright is a decommissioned hosted client and is not the SDK documented here.

The 4.x API

The current release is 4.1.0 for both languages.

• Version 4.0 requires MOSTLYRIGHT_API_KEY. Without a key, calls fail with ApiKeyRequiredError before any network request. The vendored manifest catalogs and KeylessDecayWarning were removed.
• Version 4.0 added weather.hazards (NWS alerts, storm bulletins, active tropical cyclones, and HURDAT2 best tracks, in both SDKs) and Python’s economy.release_calendar().
• Version 4.1 added wildfire incident and satellite hotspot reads to @mostlyrightmd/weather, and river-gauge reads to both SDKs. Hotspot bounding-box queries read MOSTLYRIGHT_FIRMS_MAP_KEY.

Reference coverage

The generated Python and TypeScript reference pages are built from the 4.1.0 release tags and cover the 4.x additions, including weather.hazards in both languages, Python’s economy.release_calendar(), and the TypeScript wildfires() and hotspots() reads. The upgrade guide covers releases through 3.0; the 4.0 and 4.1 breaking changes are in the changelog.

Version 3.0 set the naming contract, and it still applies:

• Daily reports use weather.daily_summaries() in Python and dailySummaries() from @mostlyrightmd/weather/daily-summaries in TypeScript. The old climate() names were removed.
• Kalshi and Polymarket expose the same market-data verbs: series, events, markets, market, candles, trades, and orderbook, except that Polymarket has no series tier.
• weather.satellite() accepts a station or arbitrary lat and lon. Europe, Africa, and the Indian Ocean now route to Meteosat and require EUMETSAT credentials unless you explicitly request VIIRS.

Date windows still use from_date / to_date; time windows use from_time / to_time. Python and TypeScript rows use the same descriptive snake_case field names.

Runtime model

The packages do not ship a fixed source manifest. Set MOSTLYRIGHT_API_KEY so the SDK can retrieve current endpoint, schema, and source definitions; the key comes with the subscription (USD 29/month at app.mostlyright.md). After resolving the manifest, the SDK fetches data directly from the selected source; Mostly Right does not proxy those source requests.

Python can cache under ~/.mostlyright/cache/, Node under ~/.mostlyright/cache-ts/, and browser builds use IndexedDB. Some sources need their own credentials, and optional hosted methods use MOSTLYRIGHT_* environment variables. See Credentials.

Where next

• Quickstart
• API reference: a compact map of the main entry points
• Python API: every public Python module and function
• TypeScript API: every public TypeScript package and export
• Upgrade guide
• Changelog