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TX-DSS v1.0

Core Concepts

TaurusX Engines

A unified engine layer that hides vendor models behind TaurusX-native names.

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Overview

TaurusX Engines are the AI model layer — the part of the system that actually generates responses. Rather than exposing raw API access to a specific vendor, TaurusX wraps all AI models behind a unified Engine Abstraction Layer.

This means that when you use TaurusX, you are using a TaurusX engine — not a named external model. The kernel chooses which model to use based on context, plan tier, and message complexity, and that choice is completely transparent to the surface.

TaurusX engine names are intentionally abstract. This allows the underlying model to be updated, switched, or improved without any change to the user experience or surface code.

Engine Abstraction Layer

The Engine Abstraction Layer (EAL) is the kernel subsystem that manages all AI model calls. Every surface — mobile chat, Continuum, TX Terminal, CLI — routes all AI requests through the EAL. No surface calls a model provider directly.

The EAL provides:

  • Model-agnostic interface — one API surface regardless of which model is underneath
  • Automatic fallback — if the selected engine is unavailable, the EAL reroutes to the next available engine
  • Consistent billing — all engine calls are metered in TaurusX Cycles regardless of underlying model cost
  • Plan enforcement — the EAL checks plan tier before dispatching; free users cannot call enterprise engines
  • Prompt injection — the EAL injects the active tone, state, and accessibility flags into every prompt automatically

Available Engines

TX Engine NameCharacterBest ForPlan Required
TX-FlashFastest, most conciseQuick answers, status checks, one-linersFree
TX-HaikuFast, balanced, efficientEveryday chat, learning, casual interactionFree
TX-SonnetSmart, capable, nuancedTechnical work, code review, planningPro
TX-OpusMost capable, highest reasoningComplex analysis, multi-step strategy, researchPro
TX-EnterpriseEnterprise-grade, highest contextLong documents, enterprise workflows, auditEnterprise
TX-KidsSafe, age-adapted, filteredKids Mode chat, Homework Helper, Vault queriesFree (Kids only)
TX-Kids is a specialised engine profile with an enforced content safety layer. It is only available to Kids Mode accounts (Tier 1 and Tier 2) and cannot be selected by adult accounts.

Routing Engine

The Routing Engine is the decision layer that sits in front of the EAL. For every incoming message, it determines which TX Engine to invoke based on:

FactorHow it influences engine selection
Message complexityShort factual questions → TX-Flash; deep analysis → TX-Opus
Active stateTechnical or Executive state prefers TX-Sonnet or TX-Opus
User planFree plan caps at TX-Haiku; Pro unlocks TX-Sonnet and TX-Opus
Explicit directive<engine:tx-opus> in message forces a specific engine
Meta-Agent activePlanning tasks always use TX-Opus regardless of plan (governed by meta-agent cycles)
Kids ModeAll requests in Kids Mode are routed to TX-Kids; no override

Engine Selection

By default, TaurusX selects the best engine for each message automatically. You do not need to choose. However, you can direct the Routing Engine explicitly using an inline directive:

<engine:tx-opus>Forces TX-Opus for this message and the remainder of the session
<engine:tx-flash>Forces TX-Flash — maximum speed, minimum tokens
<engine:auto>Returns to automatic selection (default)

Inline directives are stripped from the message before it reaches the engine. The model never sees the directive — only the cleaned message and the injected system context.

Plan Tiers & Access

PlanEngines AvailableDaily Task LimitAPI Tier
FreeTX-Flash, TX-Haiku20 tasks/dayfree
ProTX-Flash, TX-Haiku, TX-Sonnet, TX-Opus200 tasks/daypro
EnterpriseAll engines including TX-EnterpriseUnlimitedenterprise
Kids (Free)TX-Kids only10 sessions/dayfree

Billing is metered in Cycles — TaurusX's internal unit of AI consumption. Each engine has a different Cycle cost per token. The current Cycle balance is shown in the Continuum dashboard and in the Capability Panel.