Umbra · service information
What is behind a reading?
The cards, calculations and editorial decisions are different layers. Here is how they fit together.
Updated
Tarot: a real deck, not invented cards
Umbra uses the classical 78-card Rider–Waite–Smith composition: 22 major arcana and 56 minor arcana in Wands, Cups, Swords and Pentacles. Umbra’s illustrations are stylised interpretations of that tradition. Cards and meanings are upright only; reversed cards are excluded by design.
The historical reference is A. E. Waite’s The Pictorial Key to the Tarot and the Rider–Waite–Smith tradition associated with Pamela Colman Smith’s imagery. The contemporary wording, reflection prompts and contextual connections are Umbra editorial work, not quotations or statements written by Waite for your question.
How your answer is assembled
The question is first checked for topic and sensitive-question routing. A permitted question reading draws distinct cards on the server using Web Crypto randomness, without replacement within that spread. The question does not select a conveniently matching card.
The engine combines each card’s upright meaning with its position in the chosen spread, the detected topic and the editorial synthesis rules. It is a catalogue-and-rule composition, not a live human consultation or a generative AI conversation. Topic detection can miss nuance; the original question stays visible.
For an enabled private account, the daily card is drawn once for the date in your profile timezone (UTC if unset) and retained as a receipt. Refreshing does not deliberately redraw that day. Guest previews are not a promise of a cross-device daily record.
Astrology: calculation first, interpretation second
The separate Swiss Ephemeris service calculates the celestial geometry used by astrology features. Date, timezone, coordinates, house system and the selected calculation method affect the result. Missing or uncertain birth times limit what houses, angles and timing can support.
The geometry feeds an editorial layer for natal and derived charts, relationship studies, timing and specialist rules. A composite midpoint construction, a transit and a progression are different methods, not interchangeable measurements. Read the method and assumptions shown with the result.
A symbolic interpretation is not scientifically established evidence about personality, compatibility or future events. Accurate ephemerides do not validate an interpretation or remove uncertainty from the source data.
Sources and named Umbra profiles
Historical and school-specific rules are separated from Umbra’s implementation decisions. Examples include Lilly-based horary, the Umbra Ramesey + Lilly electional profile, and Shestopalov / SPbAA profession and event-formula studies. These are explicitly named readings of sources, not claims to reproduce every rule of a school or to have its endorsement.
When a source is qualitative or conflicting, an operational threshold is an editorial choice and must be labelled as such. The source-only and editorial editions may reach different or incomplete conclusions. A missing condition must not be silently treated as a confirmed match.
The linked profile notes document the horary and professions editions they name; they are not a complete reference for every Umbra module. Electional and other specialist results include their own source and decision details in the interface. Full supplied books are not redistributed here.
Question boundaries and saved results
For questions about another person’s feelings, the reading is framed through your perception rather than asserted access to their mind. High-risk requests may stop the card flow and invite you to rephrase your question yourself. Urgent safety situations point toward real-world help.
Saved receipts retain the inputs, results and method/version information provided by that flow. Reopening a saved result is not a promise of a fresh calculation with today’s rules. If the app cannot verify or interpret a saved version, it should say so rather than silently manufacture a replacement.