# Design Outline: GCP Auth Test Validation
[High-level summary of design document goals and alignment with project charter.]

## Objectives
[Clear objectives for validating the authentication flow within our own GCP project.]

## Background
[Context on prior research, existing prototypes, and business drivers.]

### Current Plan Summary
[Concise restatement of the current plan-v1 approach and scope boundaries.]

### Assumptions
[List assumptions about accounts, access, tooling, and timelines.]

## Architecture Overview
[Bird's-eye view of proposed components and their interactions.]

### Components
[Breakdown of notebooks, helper libraries, GCP resources, and dependencies.]

### Data Flow
[Sequence of OAuth exchanges, token storage locations, and IAP calls.]

## Test Environment Setup
[Steps to provision and configure the dedicated test environment.]

### GCP Project Configuration
[Project creation, API enablement, IAM policy prerequisites, and quotas.]

### OAuth Client Setup
[Process to register desktop client, manage secrets, and rotate credentials.]

### IAP Target Setup
[Plan to deploy and secure the mock IAP-protected endpoint.]

## Client Implementation
[Implementation outline for the local auth library and notebook usage.]

### Configuration Module
[Details on managing client metadata, scopes, and environment flags.]

### Authentication Flow
[Flow design covering local server behavior, browser interaction, and token persistence.]

### Request Wrapper
[Structure for wrapping HTTP calls, token refresh logic, and error handling.]

## Security Considerations
[Security controls, risk mitigations, and compliance checkpoints.]

### Secret Management
[How secrets are stored, rotated, and audited across environments.]

### Token Storage
[Requirements for local credential files, encryption options, and cleanup policies.]

### Monitoring & Alerts
[Signals for anomalous usage, quota exhaustion, or suspicious traffic.]

## Test Plan
[End-to-end validation strategy across personas and scenarios.]

### Test Scenarios
[Detailed matrix of success/failure cases, including multi-account exercises.]

### Success Criteria
[Measurable outcomes required before sharing broadly.]

### Rollback Plan
[Remediation steps if the rollout uncovers defects or regressions.]

## Operational Considerations
[Ongoing ownership, support processes, and documentation requirements.]

### Developer Experience
[Setup instructions, tooling automation, and onboarding aids.]

### Support & Maintenance
[Responsibility model, escalation paths, and update cadence.]

## Open Questions
[List of unresolved decisions, external dependencies, and follow-up research.]

## Appendix
[Supporting references, links, and glossary entries.]

### References
[Pointer to @plan-v1.md, Google documentation, and internal runbooks.]
