FateNava MCP is an MCP (Model Context Protocol) server that lets AI agents directly cast BaZi, Zi Wei Dou Shu, and Western astrological natal charts. It integrates three charting systems into a single tool, powered under the hood by FateNava's free charting API, with no account registration required, no API key, and no data stored.
Purpose This tool is aimed at AI agents or MCP clients that need fortune-telling charting capabilities. After the user provides birth information, the tool returns structured chart data for the AI to interpret further. It does not perform interpretation itself; it is only responsible for deterministic calculation.
Main capabilities
- A single tool, cast_chart, simultaneously supports BaZi (Four Pillars), Zi Wei Dou Shu, and Western astrological natal charts, and can return results for up to three systems at once.
- Deterministic calculation: the same birth information always produces the same chart, and results are calculated by a tested engine rather than generated by AI.
- True solar time correction.
- Multilingual input: city names support English, Chinese, Japanese, and Korean; birth information can also be described in a single line of text, and the API will automatically parse the date, time, place, and gender, and resolve the city into coordinates and time zone.
- Structured field input: the systems parameter can be used to select a subset of ["bazi", "ziwei", "astro"] to reduce response size (all three are returned by default).
- When the birth time is unknown: set birthTimeKnown: false, BaZi still returns three pillars, and parts that depend on the hour are omitted truthfully rather than guessed.
- Field names are in English, while traditional terms (Heavenly Stems, Earthly Branches, palaces, star names) are returned in native Chinese characters, allowing the AI agent to translate them for the user.
How to use Configure this MCP server in any MCP-compatible client (such as Cursor or a generic MCP client), then call the cast_chart tool and pass in the birth information. There are two ways to describe the birth information; choose either one:
- A single line of text (the simplest): the API will parse the date, time, place, and gender, and resolve the city into coordinates and time zone.
- Structured fields: provide fields such as date, time, place, and gender separately, and use systems to specify the charting systems needed. The API source address can be overridden via the environment variable FATENAVA_API_BASE (for testing).
Use cases
- An AI agent needs to cast a BaZi, Zi Wei Dou Shu, or Western astrological natal chart for a user.
- The chart data needs to be handed to AI for subsequent processing such as interpretation, Q&A, or synastry / marriage compatibility.
- Charting scenarios that require multilingual birth information input and true solar time correction.
Limitations and principles
- Free and anonymous: the underlying endpoint requires no login and stores nothing.
- Deterministic: charts are calculated by a tested engine, and the AI layer is only responsible for interpretation.
- Be honest about limitations: when the birth time is unknown, it degrades gracefully rather than fabricating the hour. A chart describes tendencies and themes, not fixed fate. It does not constitute medical, legal, or financial advice.
- Full interpretations, synastry, and AI Q&A require going to fatenava.com.
Regarding installation commands, specific configuration steps, supported platform details, and pricing information, the materials do not currently provide them.
