Defined terms used across the Aura documentation and codebase.
3 layers — Aura’s architectural decomposition: Sense (signal acquisition), Intelligence (four agents + orchestrator), Experience (phone, watch, earbuds, tablet surfaces). See architecture.md §2 and plan.md §10.
BMTC — Bengaluru Metropolitan Transport Corporation. The Bangalore city bus system. Aura ingests BMTC live data into commute reminders for users in Bangalore (plan.md §9.1).
Gemma 2B — Google’s open 2-billion-parameter instruction-tuned LLM. Aura uses Gemma 2B Q4_K_M as the agent-side LLM for CommsAgent and FinanceAgent, with hot-swapped LoRA adapters per agent. License: Gemma terms. https://ai.google.dev/gemma
GGUF — GPT-Generated Unified Format. The model file format used by llama.cpp. Aura ships GGUF Q4_K_M artifacts for the cross-platform llama.cpp inference path. https://github.com/ggml-org/llama.cpp
Glass-box — Adjective describing Aura’s commitment to making every autonomous or semi-autonomous action inspectable. Concretised by the Reasoning Trace.
Health Connect — Android’s unified health data platform. Aura reads HRV, sleep, HR, and steps from Health Connect on Android. https://developer.android.com/health-and-fitness/guides/health-connect
HealthKit — iOS’s unified health data platform. Aura reads HRV, sleep, HR, and steps from HealthKit on iOS. https://developer.apple.com/documentation/healthkit
HRV — Heart Rate Variability. The variation in time between heartbeats. Aura uses HRV (specifically RMSSD) as a Wellness Agent input feature for the Load Score (technical_spec.md §7.1).
IRCTC — Indian Railway Catering and Tourism Corporation. The Indian Railways ticketing system. Aura parses IRCTC PNR confirmations into the calendar (plan.md §9.1).
Knox — Samsung’s mobile-security platform offering hardware-rooted device protection and a secure execution environment. Aura’s Phase 1 deck names Knox-backed memory graph encryption as the production target (ADR-0006). https://www.samsungknox.com/en/knox-platform/whitepapers
Load Score — Aura’s composite stress / cognitive-load measure, output by the Wellness Agent. Range 0–100. Computed by an XGBoost regressor over nine features: HRV (raw + z-score), sleep debt, typing entropy, app-switch rate, notification dismiss rate, screen-on minutes, and time-of-day sin/cos. Calibrated against self-rated stress 1–5 and reported as Spearman ρ in Phase 2. (technical_spec.md §7)
LoRA — Low-Rank Adaptation. A parameter-efficient fine-tuning technique that adds small adapter matrices to selected attention projections (q_proj, v_proj, o_proj in Aura’s case). Aura trains LoRA adapters on Gemma 2B for CommsAgent and FinanceAgent on the RTX 4080. (technical_spec.md §9)
Memory Graph — Aura’s on-device structured store of the user’s history: nodes (User, Event, App, Person, Place, Transaction, Conversation, HealthSnapshot, Action, Trace) and edges (attended, sent_to, located_at, paid_to, talked_about, felt_during, triggered_by, confirmed_by_user). SQLite + sqlite-vss + SQLCipher. (technical_spec.md §6)
MLX — Apple’s array framework for ML on Apple Silicon, similar in spirit to NumPy but GPU-accelerated. Aura uses MLX as the iOS dev-time inference runtime for Gemma 2B and Phi-3-mini. https://github.com/ml-explore/mlx
NotificationListenerService — Android’s mechanism for letting an app observe system notifications. Aura’s CommsAgent reads notification metadata via NotificationListenerService. https://developer.android.com/reference/android/service/notification/NotificationListenerService
Phi-3-mini — Microsoft’s 3.8-billion-parameter compact LLM with strong tool-use behaviour. Aura uses Phi-3-mini-4k-instruct Q4 as the orchestrator’s default model (ADR-0002). https://arxiv.org/abs/2404.14219
Reasoning Trace — Aura’s structured, schema-validated record of a single decision: trigger, signals seen, candidates considered, chosen action, rationale, confirm-required flag, outcome, and any redactions. Schema in trace.v1.json (technical_spec.md §4.6). User-visible via a drawer attached to the originating action card. Retention 30 days default, user-overridable. ADR-0004.
RMSSD — Root Mean Square of Successive Differences. A time-domain heart-rate-variability metric correlated with parasympathetic nervous-system activity. Aura’s Wellness Agent reads RMSSD over a 5-minute rolling window from Health Connect / HealthKit. (technical_spec.md §7.1)
Silence Budget — Aura’s named state variable representing the daily quota of proactive non-safety surfaces. Default 3 tokens per local day; each surface consumes one token; user “Useful” tap refunds one token capped at the daily ceiling. Safety-class Wellness actions (mute, breathe, nap) are exempt. Visible as three dots in Settings; Phase 2 KPI alongside effort reduction and satisfaction. ADR-0003.
UPI — Unified Payments Interface. India’s instant real-time payment system operated by NPCI. Aura parses UPI SMS notifications from Indian banks via a regex template pack with DistilBERT fallback for unknown templates. (plan.md §9.1, technical_spec.md §3.3) https://www.npci.org.in/what-we-do/upi/product-overview
Wedge — One of Aura’s five differentiators versus the SOTA comparison row (plan.md §9): Indian life-OS depth, closed-loop biometric to action, glass-box Reasoning Trace, silence as a feature, and user-owned memory graph.
End of glossary.md.