Inspiration
Machine learning and divination are similar — they both rely on large collections of examples to decode metaphors, label symbols, use past patterns to suggest future outcomes, and have an essence of statistics. In some ways, AI even pushes beyond human limitations because of the scale of information it has learned from.
Today, many people already use GenAI for divination, but most struggle to prompt it correctly, especially for tasks like accurate hexagram calculation, and they often can’t spot errors without deep domain knowledge. Since each divination method has its own complex symbolic rules, fine-tuning prompts is hard for beginners. That gap inspired Celestial Oracle: a professional AI-powered fortune consultant with built-in expertise, offering a more personal and cost-effective way to explore divination—especially when people feel lost or need comfort.
What it does
Celestial Oracle is a personal fortune consultant that uses Gemini 3 to answer users’ questions through Meihua Yi Shu (Plum Blossom Numerology) and Tarot.
It follows pre-injected expert instructions to perform accurate complicated hexagram calculation (numerology) or fair card shuffling and drawing (tarot), then transforms those traditional metaphors into coherent, personalised readings. Users can copy or share results from the final page, and the app does not store personal data.
How we built it
Celestial Oracle is a React SPA built in Google AI Studio.
Each session is prompt-engineered: the app collects user inputs, then sanitises, validates, calculates and rate-limits them on the client before sending a structured request to Gemini. The core is a Gemini Service Adapter that injects a large domain-specific knowledge base—Meihua Yi Shu trigram/hexagram rules and Tarot symbolism—as system instructions to keep the model grounded in the intended traditions. Google Search feature is enabled for AI to add grounding for interpretation when necessary.
The app uses Gemini 3 Pro Preview for deep reasoning and multi-step synthesis, and Gemini 3 Flash Preview for faster AI-generated question inspiration. Gemini 3 Pro is configured with high thinking level to support more thoughtful, complex interpretations.
Challenges
The biggest challenge was turning traditional divination and interpretation rules into reliable, step-by-step logic. For example, Meihua Yi Shu isn’t just “three numbers = one hexagram”—it involves multiple hexagrams, changing lines (yao) that represent different possibilities, plus Five Elements relationships and Body/Function (Ti/Yong) judgement. And Tarot is not just labelling each card with some possible meaning, it is a complicated system of symbols that creates different meanings when situations vary. I had to translate that complexity into prompts and structures that Gemini could follow consistently.
Another time-consuming challenge was building the system-instruction knowledge base. I had to compile rules and meanings carefully, remove incorrect information, and watch for bias so the model wouldn’t reinforce stereotypes or produce overly deterministic readings.
I also had to balance depth vs speed. Rich interpretations can be slow, so reducing latency—without losing the “oracle” feeling—became a key part of the build.
Accomplishments
The app achieved accurate calculations and repeatable readings, which are critical for trust in divination. Even better, Gemini’s interpretations were surprisingly more coherent and context-aware than I thought AI could have done.
And I’m proud that the app looks like a real product: Gemini helped create a beautiful, celestial UI, plus a shareable result experience that feels polished and complete.
Learning
Although the responses have been quite coherent and context-aware, they are still not nuanced enough, giving generic “fortune-cookie” answers sometimes. Fine-tuning the model with feedback could potentially push the limits of AI when performing such tasks if it is possible in the future.
Also, this is my first time experimenting with AI Studio and Gemini Nano Banana Pro. It is a magical feeling that Gemini is extremely innovative, having strong opinions, compared to its good friends DeepSeek and ChatGPT, and sometimes tends to ignore the instructions with the smartness in a "border collie" way.
What's next for Celestial Oracle
• Add more divination methods (e.g., Liuren, Astro Dice, etc.)
• Expand into astrology and Bazi chart interpretation for more comprehensive self-understanding
• Use user feedback to fine-tune the model and improve consistency and accuracy
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