Tier Model — Canonical Reference
- Status: Canonical (single source of truth)
- Operationalizes: Tiered Architecture Proposal
This file is the canonical glossary for the tiered architecture (T0–T5). Tier IDs, stage names, boundaries, the autonomy ladder, the fleet vocabulary rules, and the cross-document link/anchor contract are defined here once and consumed everywhere else.
[!IMPORTANT] Treat this file as read-only canonical truth. Downstream documentation (architecture, roadmap, getting-started, recipes) must cite the tier IDs, names, vocabulary, and anchors defined here rather than redefine them. If a tier boundary or name needs to change, change it here first.
Naming Convention
Each tier carries a stable ID (T0–T5) and a stage name. The two are paired everywhere:
T#IDs are canonical. Use them for every boundary reference, graduation note, and cross-document anchor. They never change, so links stay deterministic.- Stage names are user-facing labels. Use them in prose and headings for readability.
The pairing is always written T# — Name (for example, T0 — Dev).
Canonical Tier Table
T0 is the documented default starting path. T2 is the recommended production path. T3–T5 are advanced. Infra details are drawn from Section 5 of the proposal.
| T# | Stage name | Operator reach / scope | Edge infra | Cloud infra | One-line purpose |
|---|---|---|---|---|---|
| T0 | Dev | Laptop + 1 robot (default) | ROS 2 + Docker only | None | The honest zero-cloud, zero-Kubernetes floor for the full training lifecycle. |
| T1 | Lab | One site, a few robots, shared GPU | Shared disk (NFS/SMB) | One Blob storage account (optional AzureML / MLflow) | Add the first cloud resource, storage, for a small lab or integrator. |
| T2 | Pilot | One site, at scale, team (recommended) | None beyond Docker | AzureML + storage + model registry + MLflow | Cloud training, registry, and shared catalogs become the default. |
| T3 | Production | Single site, declarative deployment | Local k3s + FluxCD | Same as T2 (no Arc) | GitOps deployment automation at one site, proving Arc is not required. |
| T4 | Scale | Multiple sites you cannot directly reach | Arc + AKS/Flux + gating | T2 + cross-site connectivity / identity | Multi-site fleet delivery terminus; Arc as reachability/identity broker. |
| T5 | Operate | Fleet-wide cognition (roadmap) | + Azure IoT Operations | + Fabric Real-Time Intelligence + drift/retraining | Fleet intelligence: roadmap capability for drift detection and retraining. |
Full training lifecycle (the anchor goal): capture demonstrations on a robot, train an imitation policy, validate it, and run that policy back on the robot, the full loop for one task. The full training lifecycle is fully achievable at T0-T2 with manual deployment and no Kubernetes, Arc, or fleet infrastructure. Data augmentation is a separate optional axis (A0-A2), not a step in the full training lifecycle.
Boundaries
- Multi-site boundary (Arc): falls between T3 and T4. Arc becomes necessary only when robots span multiple sites you cannot reach from a single operator network.
- Intelligence boundary: falls between T4 and T5. T4 delivers and gates policies; it does not run drift detection, retraining, or aggregate analytics. Those are T5.
[!NOTE] Roadmap honesty. T5 (Operate / fleet intelligence) is on the roadmap and not yet available. The fleet-intelligence domain is currently specified, with implementation planned. Label this status explicitly in both contributor and user-facing docs.
The Autonomy Ladder (T5.0–T5.3)
Autonomy is a different axis from T0–T4. T0–T4 scale on infrastructure reach (sites, GPU, collaboration); T5.0–T5.3 scale on decision authority / loop closure. They are orthogonal: a single-site T3 operator can sit at T5.0, and a multi-site T4 operator can remain fully manual. The autonomy stages are how much of the retraining decision a human delegates, not more infrastructure to buy.
| Rung | Decision authority | Human role | Status |
|---|---|---|---|
| T5.0 | Gated retraining: the system surfaces signals only; humans trigger retraining. | Human triggers every retraining cycle | Not built |
| T5.1 | Human-in-the-loop / active learning: the system proposes what to retrain on and when. | Human approves each cycle | Ad-hoc (Hex) |
| T5.2 | Continual learning: the system retrains on a schedule or trigger. | Human reviews before deployment | Not built |
| T5.3 | Autonomous closed-loop: the system detects drift, retrains, gates, and deploys. | None (fully autonomous) | Not built |
[!WARNING] Fully autonomous retraining on production data is a foot-gun: a legitimate distribution change can cause the loop to bake current degraded behavior into the next dataset, and drift detection needs statistical power that only exists at fleet scale. T5 should default to human-supervised (T5.0–T5.1), not closed-loop (T5.3). T5.3 stays a roadmap direction, not a near-term target.
Vocabulary Rules
These rules are mandatory across all documentation.
- "Fleet" means a fleet of robots only. It never refers to Kubernetes clusters, nor to Azure Kubernetes Fleet Manager (a distinct Azure product for managing a fleet of clusters, not robots). Cluster-level concerns are always written as "clusters" or "sites," never "fleets."
- Fleet delivery (T4) is the delivery and connectivity control plane: getting a validated policy onto robots across sites you cannot directly reach, with a safety gate before a policy swaps on a physical arm. This is the necessary multi-site concern.
- Fleet intelligence (T5) is the cognition layer: drift detection, automated retraining triggers, and aggregate telemetry analytics. This is the roadmap/placeholder concern.
- Banned phrase: "fleet management". Do not use it. The Kubernetes ecosystem (Azure Kubernetes Fleet Manager, FluxCD, Argo, Rancher Fleet) uses "fleet" for the cluster delivery/placement concern, so the bare phrase collides with Azure Kubernetes Fleet Manager and re-welds the two concerns this model deliberately separates. Always qualify as fleet delivery or fleet intelligence instead.
Link / Anchor Contract
This section defines the canonical file paths and exact heading anchors that downstream documentation uses when linking across the tier model, architecture, roadmap, and recipe entry points.
Anchor Convention
Anchors follow GitHub / markdownlint (MD051) rules, applied to the heading text (the T# — Name
pairing, not the surrounding prose):
- Lowercase the text.
- Drop all punctuation that is not a hyphen — this includes the em-dash (
—) and any trailing period. The em-dash is removed, but the spaces on either side of it remain (step 3). - Replace each remaining space with a hyphen.
So T0 — Dev → lowercased t0 — dev → em-dash dropped leaves t0 dev (two spaces) → spaces to
hyphens → t0--dev. The double hyphen comes from the two spaces that flanked the dropped em-dash.
[!IMPORTANT] Headings in
architecture.mdmay carry descriptive trailing text (for example,### T0 — Dev. One robot, one laptop). The anchor is computed from the full heading text, so a heading with trailing prose produces a longer anchor. To keep anchors deterministic and short, the linkable tier sections use the exact headings published below:### T# — Name, with any descriptive sentence moved into the body text beneath the heading.
Architecture Tier Anchors
File: docs/contributing/architecture.md. The architecture document exposes one ### heading per
tier, worded exactly as the "Heading" column, yielding the "Anchor" column. Link as
docs/contributing/architecture.md#<anchor>.
| T# | Heading (verbatim) | Anchor |
|---|---|---|
| T0 | ### T0 — Dev | #t0--dev |
| T1 | ### T1 — Lab | #t1--lab |
| T2 | ### T2 — Pilot | #t2--pilot |
| T3 | ### T3 — Production | #t3--production |
| T4 | ### T4 — Scale | #t4--scale |
| T5 | ### T5 — Operate | #t5--operate |
Roadmap Anchors
File: docs/contributing/ROADMAP.md. The roadmap document exposes the autonomy-ladder section with
the heading below. Link as docs/contributing/ROADMAP.md#<anchor>.
| Section | Heading (verbatim) | Anchor |
|---|---|---|
| Autonomy ladder | ## The Autonomy Ladder (T5.0–T5.3) | #the-autonomy-ladder-t50t53 |
[!NOTE] In the autonomy-ladder anchor the parentheses and dots are dropped and the em-dash inside
T5.0–T5.3is removed, collapsing it tot50t53. Use the anchor string verbatim from the table.
Recipe Filenames / Paths
Directory: docs/recipes/. The naming scheme is one directory per tier, named
tier-<n>-<slug>/, each containing a README.md entry point. The slug is the lowercased stage name.
Entry pages and cross-links use these exact paths.
| T# | Recipe path | Status |
|---|---|---|
| T0 | docs/recipes/tier-0-dev/README.md | Default tier |
| T1 | docs/recipes/tier-1-lab/README.md | Available |
| T2 | docs/recipes/tier-2-pilot/README.md | Recommended |
| T3 | docs/recipes/tier-3-production/README.md | Advanced |
| T4 | docs/recipes/tier-4-scale/README.md | Advanced |
| T5 | docs/recipes/tier-5-operate/README.md | Roadmap |
[!NOTE] The existing topic-based recipe folders (
docs/recipes/training/,docs/recipes/data-collection/) are owned by their current authors and are unchanged by this work. The per-tier folders above are new and additive.
Getting-Started Entry Anchors
Files: README.md (repo root), docs/README.md, docs/getting-started/. These entry points expose
the headings below so other docs can deep-link to the tier picker. Link as <file>#<anchor>.
| Entry point | File | Heading (verbatim) | Anchor |
|---|---|---|---|
| Tier picker (on-ramp) | docs/getting-started/README.md | ## Choose Your Tier | #choose-your-tier |
| Default path (T0) | docs/getting-started/README.md | ### Start Here — T0 Dev | #start-here--t0-dev |
| Quick Start | docs/getting-started/quickstart.md | ## Quick Start | #quick-start |
Cross-Cutting Augmentation Axis (Reference)
Data augmentation is an optional axis orthogonal to T0-T5, recommended only when data is scarce. It is not part of the full training lifecycle, and the A0-A1 build is deferred. Listed here for vocabulary completeness only.
| Stage | Approach | Where it runs |
|---|---|---|
| A0 | Classical CV augmentation (crops, jitter, blur, photometric/geometric) | Local, CPU, no model |
| A1 | Local small-VLM generation (e.g. vLLM locally, or Azure AI Foundry) | Local GPU or hosted endpoint |
| A2 | Full Cosmos / SDG world-foundation-model pipeline | Cloud, GPU cluster |