Privacy-first data architecture

Three isolated layers separate PII from AI. Personally identifiable data never leaves the vault. Downstream AI services see only anonymised, banded profiles keyed by hashed IDs.

Architecture

Layer 1

PII Vault

·name, email, phone
·encryption-at-rest (sim.)
·access: vault API only

Contains PII

Layer 2

Context Layer

·anon_id ⇄ vault_id
·no PII returned
·binds + resolves only

No PII

Layer 3

AI Processing

·banded inputs (income/budget)
·MCP endpoints
·scoring + recommendations

No PII

Boundary contract: The AI layer never receives names, emails, phones, addresses or raw IDs. Inputs are banded (income_band, budget_band, age_band) and keyed by an opaque anon_id generated by SHA-256 over vault_id + salt.

Anonymous subject

Hashed ID — no name, email or phone is exposed to the AI layer.

/get-credit-bandMCP

{
  "anon_id": "anon_…",
  "credit_band": "B+",
  "score_range": "680–720",
  "pii_exposed": false
}

preview — click Call MCP endpoints

/get-affordabilityMCP

{
  "anon_id": "anon_…",
  "affordability_score": 82,
  "budget_ratio": "13%",
  "pii_exposed": false
}

preview — click Call MCP endpoints

/get-vehicle-matchMCP

{
  "anon_id": "anon_…",
  "matches": [
    "BMW X3",
    "Audi Q5",
    "VW Tiguan"
  ],
  "pii_exposed": false
}

preview — click Call MCP endpoints

/get-intent-scoreMCP

{
  "intent_score": 78,
  "time_to_buy": "7–14 days",
  "return_visits": 3
}

preview — click Call MCP endpoints

PII accessed in last 24h: 0 times— AI services received only anonymised data.

Audit log

Every cross-layer access is recorded

Time	Layer	Endpoint	Anon ID	Purpose	PII?
No audit entries yet.

Data minimisation

AI receives only banded / hashed fields. Raw values never cross the boundary.

Vault isolation

PII is stored in a separate layer with its own access policy and audit trail.

GDPR-ready

Right-to-erasure works by deleting the vault row; AI artefacts hold no PII.