# FernWX

> FernWX saves many weather providers' forecasts for a place and time, keeps every run unchanged, and verifies them against what actually happened. Agents can read an account's ledger through a remote MCP server or a REST Agent API described by OpenAPI 3.1.

- MCP server (remote, Streamable HTTP): https://fernwx.com/api/mcp. 85 tools: one per documented GET operation (84) plus `fernwx_whoami`. Hosts that discover credentials (claude.ai, ChatGPT) are walked through OAuth 2.1; others send `Authorization: Bearer fwx_<prefix>_<secret>`.
- REST Agent API: https://fernwx.com/api/openapi.json is the OpenAPI 3.1 contract (snapshot 0.1.0+84.27e39098). Keyed routes take the same bearer key; `/api/public/forecast` is the keyless live-weather read and is IP rate-limited. Without authentication, other weather routes may return HTTP 200 synthetic examples. Always check `example`; never use `example: true` as live or account weather.
- OAuth scope names are stored, not yet enforced as tool-level limits. A token can access all documented reads allowed by its owning account; requesting only `public:read` does not restrict it to public tools.
- Documented reads enforce the account's permissions. No arbitrary SQL. Every documented operation and MCP tool is a read. Some reads update last-seen timestamps or stale report state, and saved-insight runs append query activity logs; MCP tools declare these side effects.
- A key or OAuth token is not read-only. It can also call account routes outside the documented contract that write: generate and save AI explanations of soundings and NWS text products and sounding comparison syntheses (these count against the account’s AI usage limits), generate speech audio, import radiosonde soundings into the account (overwrite mode replaces the account’s own earlier imports), and request or release temporary restores of archived days. Each is limited to the owning account and bounded. It cannot change locations, settings or keys, trigger collectors, create or edit saved reports, Run Books, dashboards or insights, or delete the cold archive.
- The Research Lab ("Forecast Ledger Intelligence", /ai-sql) is FernWX's own built-in agent for signed-in users. It is not the external interface; external agents use the MCP server or the Agent API.

## Developer docs

- [Developers & AI agents](https://fernwx.com/developers): MCP setup, authentication, OAuth, boundaries
- [Interactive API reference](https://fernwx.com/docs): every operation, parameter and response schema
- [OpenAPI 3.1 document](https://fernwx.com/api/openapi.json): machine-readable contract
- [API catalog](https://fernwx.com/.well-known/api-catalog): RFC 9727 linkset
- [OAuth protected-resource metadata](https://fernwx.com/.well-known/oauth-protected-resource/api/mcp): RFC 9728, for the MCP server
- [OAuth authorization-server metadata](https://fernwx.com/.well-known/oauth-authorization-server): RFC 8414

## About FernWX

- [Knowledge Base](https://fernwx.com/about): forecast memory, verification, data sources and methods
- [FernWX for NWS offices](https://fernwx.com/about/nws)
- [Data sources and attribution](https://fernwx.com/attribution)

## Optional

- [Severe weather (example)](https://fernwx.com/severe-weather)
- [NWS text products (example)](https://fernwx.com/text-products)
- [Maps](https://fernwx.com/maps)