Personal Instruments
Private alpha

Contextator

A local-first context vault that lets a person approve exactly what their phone shares with a browser tool.

Category: Personal Instruments
Platform: iPhone + Chrome
Status: Private alpha

Reuse personal context without surrendering the vault.

The phone remains the source of truth. Reviewed context items become persona-specific packages, and an encrypted relay delivers only the payload the person inspects and approves.

User value

Personalization with a visible boundary.

Reuse preferences, constraints, and current context without giving every destination a permanent profile.

Keep the vault on the phone

Journal entries, reviewed context, personas, packages, and audit history remain under the iPhone's control.

Review the exact payload

See included items, exclusions, purpose, destination, and outgoing text before approval.

Share only what is needed

The browser requests a persona package, receives approved text, inserts it, and does not submit the page.

Features

A vault built around review.

Every stage separates captured text from accepted context and accepted context from disclosure.

01
Local journal
Capture notes on the iPhone without sending them to a model or remote context service.
02
Reviewed context items
Approve, edit, or reject deterministic suggestions before they become verified context.
03
Persona packages
Generate purpose-specific context for AI Assistant, Professional, or Traveler use.
04
Explainable exclusions
See why expired, unverified, restricted, or overly sensitive items were left out.
05
Authenticated local copy
Review and edit a package, then use device authentication before copying it.
06
Encrypted browser requests
Pair Chrome, review a request on the phone, and approve or deny the outgoing package.
07
Metadata-only audit
Record relevant sharing events without storing the outgoing package content in the audit log.

How it works

From note to approved insertion.

Context is prepared where it is owned and disclosed only after review.

01
Capture
Write a journal entry or manage a context item directly on the phone.
02
Verify
Review deterministic proposals and block restricted information before saving.
03
Package
Apply persona, validity, verification, category, and sensitivity rules.
04
Request
Ask for that persona from a paired Chrome extension with an editable field focused.
05
Approve
Inspect and edit the exact payload, then authenticate, deny, or let the request expire.
06
Insert
Decrypt the approved response in Chrome and place the text without submitting the form.

Product concept

Personalization is a disclosure decision.

Useful continuity does not require every service or browser helper to own a complete personal profile.

The phone is authoritative

Destinations can request context, but they do not hold or query the complete vault.

Captured text is not truth

Deterministic extraction creates proposals. The person decides what becomes verified context.

Personas limit disclosure

Each purpose selects allowed categories and excludes context that is too sensitive, stale, or uncertain.

Architecture

Storage, request, approval, and insertion stay separate.

The relay connects the phone and browser without becoming a readable context store.

01Journal and reviewed phone vault
02Persona package generation
03Encrypted Chrome request
04Temporary relay queue
05Phone review and authentication
06Encrypted approval or denial
07Focused-field insertion without submission

Ciphertext-only message bodies

Client endpoints perform key agreement and authenticated encryption. The relay routes envelopes without the payload keys.

Deterministic local extraction

The current parser uses explicit rules and no local or remote language model.

Safe browser boundary

Extension access is user initiated, targets a supported editable field, and never intentionally submits the page.

Technology

A local vault with an encrypted handoff.

iPhone

Swift
SwiftUI
CryptoKit
LocalAuthentication
iOS 17+

Chrome

TypeScript
Manifest V3
Vite
Active-tab insertion
chrome.storage.local

Relay

Node.js
Fastify
In-memory development store
Redis-compatible store

Security

AES-GCM
X25519
HKDF-SHA256
iOS Keychain
Metadata-only audit

Development

The integration alpha is implemented.

The vault, deterministic parser, personas, Chrome extension, shared protocol, encrypted relay, approval flow, and audit model exist. Physical end-to-end validation and release hardening remain incomplete.

Stage: Private alpha
Clients: iPhone + Chrome
Extraction: Deterministic
Physical golden path: Not yet signed off

Implemented

SwiftUI vault with journal, reviewed context, personas, package review, authenticated copy, pairing, requests, and audit history
Restricted-content blocking, duplicate checks, validity and sensitivity rules, and explainable exclusions
AES-GCM encrypted local collections with Keychain-held iOS key material
Manifest V3 Chrome extension with pairing, active-field detection, encrypted requests, and safe insertion
Fastify relay with pairing, expiry, revocation, encrypted queues, and in-memory or Redis-backed storage
X25519, HKDF-SHA256, and AES-GCM envelope encryption with automated protocol and privacy coverage

Alpha hardening

Add a release-safe vault unlock, complete and record the physical iPhone and Chrome golden path, validate a production-like HTTPS relay, and finish key-storage, permission, privacy, and release review.

Contextator lab notes

The project, over time.

Notes about the thinking, architecture, development, and decisions behind this work.

Contextator

Personalization with a visible boundary.

Keep the vault on the phone

Review the exact payload

Share only what is needed

A vault built around review.

Local journal

Reviewed context items

Persona packages

Explainable exclusions

Authenticated local copy

Encrypted browser requests

Metadata-only audit

From note to approved insertion.

Capture

Verify

Package

Request

Approve

Insert