pre.dev-spec.md

Executive Summary

Build a Perplexity-style AI-powered answer engine web application that lets users ask natural-language questions and receive AI-generated answers with clickable source citations. Key features: search interface, LLM integration (GPT-4 or similar) for structured answers, web search API integration for real-time sources, source snippets and links, conversational follow-ups, related question suggestions, streaming token responses, history storage, responsive minimalist UI. Tech stack: Next.js, TypeScript, LLM API (OpenAI/Anthropic), web search API (Serper/Brave), database for histories, streaming APIs for tokenized responses, SEO-friendly architecture. Objectives: provide accurate, well-cited answers by combining web sources and AI reasoning; deliver fast, mobile-friendly UX with history and multi-turn context. Expected outcomes: production-ready MVP supporting query-to-answer flow with citations, streaming, conversation history, and clean UI; roadmap for scaling and improved retrieval accuracy.

Core Functionalities

• Search Interface: Clean, modern UI with a prominent search bar for user queries, instant suggestions, and responsive design. (Priority: High)
• AI-Powered Answers: Integrate an LLM (e.g., GPT-4) to generate comprehensive, structured answers combining retrieved web sources. (Priority: High)
• Web Search & Citations: Real-time web search integration using APIs (Serper/Brave), scraping relevant sources, extracting snippets, and presenting clickable citations. (Priority: High)
• Conversational Context & History: Support multi-turn conversations with context retention, related question suggestions, and persistent user history in a database. (Priority: High)
• Streaming & UX Enhancements: Token-by-token answer streaming, smooth animations, mobile-responsive design, and SEO-friendly Next.js architecture. (Priority: Medium)

Tech Stack

• Frontend: Next.js, React, React Query or SWR
• Frontend/Backend: TypeScript
• Styling: Tailwind CSS
• AI Processing: OpenAI GPT-4
• Backend: Serper API, WebSocket / Server-Sent Events (SSE), tRPC (preferred) or Next.js API Routes, OpenAPI / RapidAPI
• Testing: Puppeteer or Playwright
• Database: Pinecone or Milvus, Prisma
• Database Management: PostgreSQL
• Storage: Supabase Storage or AWS S3
• User Authentication: Clerk
• Hosting: Vercel
• Error Monitoring: Sentry
• Data Storage: Redis

Development Guidelines & Best Practices

Follow these guidelines while implementing the project:

• Placeholder Images: Use Unsplash or Picsum Photos for placeholder images
  • Example: https://source.unsplash.com/random/800x600?nature
  • Example: https://picsum.photos/800/600
• Code Quality: Write clean, maintainable code with proper comments and documentation
• Testing: Test each feature thoroughly before marking it as complete
• Commit Messages: Use clear, descriptive commit messages that reference the task/story ID
• Error Handling: Implement proper error handling and user-friendly error messages
• Responsive Design: Ensure all UI components work across mobile, tablet, and desktop devices
• Accessibility: Follow WCAG guidelines for accessible UI components
• Performance: Optimize images, minimize bundle sizes, and implement lazy loading where appropriate
• Security: Never commit API keys or sensitive credentials; use environment variables
• API & Model Versions: Always use the latest available APIs and models unless the user explicitly specifies a different version
• Progress Updates: Update task checkboxes in real-time as you work through the plan

Project Timeline

This plan lays out your roadmap in Milestones, Stories with acceptance criteria, and Subtasks. Follow the plan task by task and update progress on milestones, stories, and subtasks immediately as you work on them based on the legend below.

Progress Legend:

• - [ ] = To-do (not started)
• - [~] = In progress (currently working on)
• - [x] = Completed (finished)
• - [/] = Skipped (not needed)

Tasks are categorized by complexity to guide time estimations: XS, S, M, L, XL, XXL.

- [x] Milestone 1: Project setup: repo, Next.js + TypeScript scaffold, design system, CI/CD, env secrets, basic routing

• Setup Project Repository - (XS): As a: DevOps engineer, I want to: set up a new project repository with initial structure and CI hooks, So that: the team has a clean starting point for all future work
  • Acceptance Criteria:
    • Repository created with README and contribution guidelines Git ignore configured for common environments Initial branch and permissions set CI pipeline file present and wired to trigger on push Repository accessible in project tooling
• Configure Environment Variables - (S): As a: DevOps engineer, I want to: define and secure environment variables for development and production, So that: applications run with correct configurations and secrets are protected
  • Acceptance Criteria:
    • Env vars defined for DEV and PROD Secrets stored securely in vault/secret manager Tooling validates variable presence at startup No hard-coded secrets in code Documentation updated with variable names and usage
• Initialize Database Schema - (M): As a: Backend engineer, I want to: initialize the database schema for core entities, So that: data can be stored and retrieved for MVP features
  • Acceptance Criteria:
    • Schema files created for core entities Migrations configured and runs on deploy Seed data script available Indexes defined for common queries Connection strings stored securely
• Configure LLM & Search API Keys - (S): As a: DevOps engineer, I want to: configure and securely store API keys for LLM and search services, So that: the system can query external AI services without exposing credentials
  • Acceptance Criteria:
    • API keys stored securely in vault Access restricted to necessary services Keys rotated on a schedule Audit logs for usage captured No keys in source control
• Initialize TypeScript & Next.js - (S): As a: Developer, I want to: bootstrap TypeScript and Next.js project structure, So that: there is a solid, scalable frontend scaffold
  • Acceptance Criteria:
    • tsconfig.json present with strict settings Next.js app bootstrapped with pages and basic routing eslint/prettier configuration Build script and ts-node integration optional Type safety warnings handled during initial compile
• Setup Streaming API Infrastructure - (L): As a: Platform engineer, I want to: provision streaming APIs (e.g., WebSockets, Pub/Sub), So that: the system can handle real-time data flows for MVP features
  • Acceptance Criteria:
    • Streaming endpoints deployed Authentication enforced for streams Latency and throughput benchmarks Scaling strategy defined Monitoring and alerts in place

- [x] Milestone 2: Authentication and role management for users and admins, including accounts, permissions, and settings

• Settings: Export History - (M): As a: user, I want to: export history data, So that: I can back up or share my activity
  • Acceptance Criteria:
    • User can initiate export Export file contains complete history data Export format is selectable (e.g., CSV/JSON) Export operation handles large datasets gracefully
• Settings: Manage API Keys - (S): As a: user, I want to: manage API keys in Settings, So that: I can securely configure external integrations
  • Acceptance Criteria:
    • User can add an API key User can edit an existing API key User can delete an API key Keys are stored securely (mock encryption)
• Settings: Conversation Privacy - (S): As a: user, I want to: configure conversation privacy settings, So that: my conversations respect my privacy preferences
  • Acceptance Criteria:
    • User can toggle privacy on/off for conversations Changes apply to new conversations Default privacy applies to existing conversations Privacy settings are saved securely
• Settings: Default Search Engine - (S): As a: user, I want to: set a default search engine, So that: searches from the app use the chosen engine by default
  • Acceptance Criteria:
    • User can select from a list of search engines Selected engine is saved and applied to searches Preference persists across sessions Edge cases: unsupported engines are rejected gracefully
• Settings: Toggle Dark Mode - (XS): As a: user, I want to: toggle dark mode in Settings, So that: the app UI adapts to lighting preferences for better usability
  • Acceptance Criteria:
    • User can toggle dark mode on and off in Settings UI theme updates immediately upon toggle Preference is persisted across app restarts

- [x] Milestone 3: Search input, query handling, web search API integration, real-time scraping/ingest and source retrieval

• Conversational Follow-ups - (M): As a: user, I want to: continue the conversation with additional questions, So that: I can drill down to more precise information
  • Acceptance Criteria:
    • User can ask follow-up questions System retains conversation context across turns Context window handles long conversations Follow-up answers reflect previous context
• History Storage - (S): As a: user, I want to: store my search history for quick access later, So that: I can revisit past queries
  • Acceptance Criteria:
    • Searches stored per user History persists across sessions Privacy controls for history deletion Option to pin/favorite important queries
• Answer Generation - (S): As a: user, I want to: get a concise answer generated from the query, So that: I receive an immediate, understandable response
  • Acceptance Criteria:
    • Answer is produced within 1-2 seconds Answer relevance score above threshold Supports follow-up clarifying questions Handles ambiguous queries by asking a clarifying question
• Streaming Answers - (L): As a: user, I want to: receive streaming responses as they are generated, So that: I can start consuming information before the full answer is ready
  • Acceptance Criteria:
    • Partial chunks arrive in order Latency for first chunk within X seconds Backpressure handling when user interrupts Final complete answer delivered with no loss of earlier chunks
• Responsive UI - (XS): As a: user, I want to: see an interface that adapts to my device, So that: I can search effectively on any screen size
  • Acceptance Criteria:
    • Layout adapts to mobile/tablet/desktop Accessible controls and readable text Performance keeps search results rendering quickly UI maintains consistency with theming and branding
• Search Input - (XS): As a: knowledge-seeking user, I want to: enter a query into a search field and receive relevant results, So that: I can quickly find information relevant to my question
  • Acceptance Criteria:
    • Query accepted and non-empty Results list is returned with at least 5 items System handles special characters and whitespace gracefully Edge case: empty query shows helpful prompt or suggested searches
• Streaming Responses - (L): As a: user, I want to: see streaming responses while I ask questions, So that: I get near-instant feedback and maintain engagement
  • Acceptance Criteria:
    • User sees streaming chunks progressively as answers are generated Streaming stops gracefully with final completion state System handles network interruptions by buffering and resuming streaming No data duplication or out-of-order chunks in the stream
• History - (S): As a: user, I want to: view and search my previous interactions in the answer page, So that: I can reference past answers and track progress
  • Acceptance Criteria:
    • User can access history panel from Answer Page History displays a list of past interactions with timestamps User can search and filter history by keyword and date Selecting a history item loads the corresponding answer without losing current session History data is persisted across sessions

- [x] Milestone 4: Conversational UI, multi-turn context management, streaming LLM responses, related questions suggestions

• Search Query - (S): As a: user, I want to: search for information within the conversation context, So that: I can retrieve relevant data to inform the answer
  • Acceptance Criteria:
    • User submits a non-empty query and receives relevant results System returns results within 1-2 seconds Search results are ranked by relevance to the query Edge case: empty or whitespace query returns guidance to enter a term
• Generate Answer - (M): As a: user, I want to: generate an answer based on the search results and context, So that: I can obtain a helpful, concise response
  • Acceptance Criteria:
    • Response is generated within acceptable latency (<2s) Answer is coherent and references search results where applicable No-sensitive data leakage; only share appropriate content User can request a longer or summarized answer
• Stream Responses - (L): As a: user, I want to: receive streaming responses as the answer is generated, So that: I get real-time feedback and improved perceived latency
  • Acceptance Criteria:
    • Chunks arrive in correct order No data loss during streaming Partial chunks render progressively User can pause/resume streaming
• Show Citations - (S): As a: user, I want to: display citations for the generated answer, So that: I can verify sources and trust the information
  • Acceptance Criteria:
    • Citations are visible and linked Citations correspond to referenced parts of the answer Missing sources are indicated gracefully Citations update if answer is regenerated
• Follow-up Context - (S): As a: user, I want to: provide follow-up context or clarifications, So that: I can refine future responses
  • Acceptance Criteria:
    • Follow-up input is captured Future responses consider follow-up context No loss of prior context when new input is provided System prompts for missing context when insufficient information exists
• Save Conversation - (S): As a: user, I want to: save the conversation history, So that: I can reference it later or share with others
  • Acceptance Criteria:
    • Conversation is persisted in user account or local storage Save operation confirms success Saved data includes question, answer, and citations Privacy controls respected and accessible

- [x] Milestone 5: Landing, Answer page UI, responsive design, history storage and retrieval, mobile-first design

• Search Bar - (M):
  • Acceptance Criteria:
    • Story functionality is implemented as specified User interface is responsive and accessible Data is properly validated and stored Error handling provides helpful feedback
• AI Answers - (M):
  • Acceptance Criteria:
    • Story functionality is implemented as specified User interface is responsive and accessible Data is properly validated and stored Error handling provides helpful feedback
• Source Citations - (M):
  • Acceptance Criteria:
    • Story functionality is implemented as specified User interface is responsive and accessible Data is properly validated and stored Error handling provides helpful feedback
• Related Questions - (M):
  • Acceptance Criteria:
    • Story functionality is implemented as specified User interface is responsive and accessible Data is properly validated and stored Error handling provides helpful feedback
• Conversation History - (M):
  • Acceptance Criteria:
    • Story functionality is implemented as specified User interface is responsive and accessible Data is properly validated and stored Error handling provides helpful feedback
• Responsive Design - (M):
  • Acceptance Criteria:
    • Story functionality is implemented as specified User interface is responsive and accessible Data is properly validated and stored Error handling provides helpful feedback
• Export History - (S): As a: user, I want to: export my conversation history to a downloadable file, So that: I can save or share conversations for offline access
  • Acceptance Criteria:
    • User initiates export from history view Export includes selected conversations and metadata Export file is generated in a standard format (JSON/CSV) Downloaded file integrity verified (size >0, valid JSON/CSV) Unauthorized users cannot export others' history
• Delete Entry - (S): As a: user, I want to: delete a specific conversation entry, So that: I can manage my history and protect privacy
  • Acceptance Criteria:
    • User can select one or more conversations to delete System prompts confirmation before deletion Deletion is irreversible and reflected in UI within 1-2 seconds Audit trail entry created for deletion action Edge case: deleting last entry leaves UI in consistent state
• Conversation Recall - (XS): As a: user, I want to: recall previous conversations or retrieve a past chat context, So that: I can reference important details or continue a dialogue seamlessly.
  • Acceptance Criteria:
    • User can fetch a list of past conversations System returns context for selected conversation within 2 seconds Retrieved context matches the original chat content without corruption Edge case: no match returns a clear message and no data leakage Data is loaded from a cached/secure store and not exposed to unauthorized users
• Pin Conversation - (S): As a: user, I want to: pin a conversation to top for quick access, So that: I can easily access important chats
  • Acceptance Criteria:
    • User can pin/unpin conversations Pinned state persisted across sessions Pinned order reflected in history view Unintended pinning does not occur Performance impact on large histories remains minimal

- [ ] Milestone 6: Admin dashboard for monitoring, metrics, and content moderation tools

• Admin Dashboard Overview - (S): As a: Admin, I want to: view a comprehensive dashboard overview with key metrics, so that: I can monitor system health and usage at a glance.
  • Acceptance Criteria:
    • Dashboard loads within 1 second under normal load Key metrics (active users, requests per minute, error rate) display correctly Filters (time range, scope) update metrics without reload Sensitive data masked appropriately State persists across navigation
• Manage Sources - (M): As a: Admin, I want to: manage data sources (add/edit/delete), so that: I can control where data is ingested and displayed on the platform.
  • Acceptance Criteria:
    • Add new source via form with validation Edit source metadata updates in real time Delete source prompts confirmation and handles cascade effects Source connection test can be run and reports result Audit trail of changes is stored
• Conversation Moderation - (L): As a: Admin, I want to: review and moderate conversations flagged by users or automated systems, so that: I can uphold community standards.
  • Acceptance Criteria:
    • Flagged conversations appear in moderation queue Moderators can approve, reject, or escalate with reason Actions are logged with timestamps and moderator identity Moderation decisions update user status and metrics System supports bulk actions for multiple items
• Deploy & API Keys - (L): As a: Admin, I want to: manage deployments and API keys, so that: I can secure integrations and control access to features.
  • Acceptance Criteria:
    • API keys can be created, rotated, and revoked Deployment workflow integrates with CI/CD Keys are stored securely and access is auditable Credential exposure is prevented in UI logs Restricted environments enforce key scoping and expiration
• Analytics & Usage - (M): As a: Admin, I want to: access analytics dashboards to monitor platform usage, so that: I can make data-driven decisions.
  • Acceptance Criteria:
    • Dashboards render with correct metrics across roles Data refresh cadence configurable Export of analytics data in CSV/JSON Metrics can be filtered by segment and time range Access controls restrict sensitive analytics

- [ ] Milestone 7: Documentation, deployment pipelines, release notes, and production roll-out

• Setup CI Pipeline - (S): As a: DevOps engineer, I want to: set up a continuous integration pipeline, So that: code changes are automatically built and tested before deployment
  • Acceptance Criteria:
    • CI pipeline triggers on commit to main branch Build completes successfully for at least 90% of runs Tests run in CI without flaky failures Artifacts are stored with version tags Pipeline configuration is stored in version control
• Configure Environment - (S): As a: Platform administrator, I want to: configure environment variables and runtime settings for deployments, So that: applications have the correct configuration per environment
  • Acceptance Criteria:
    • Environments (dev/stage/prod) have distinct configurations Sensitive values are stored securely (vault/secrets manager) Deployment tools reference correct environment variables in builds Validation job confirms environment readiness before deployment
• Deploy Infrastructure - (M): As a: Cloud engineer, I want to: provision and deploy infrastructure via IaC, So that: required resources exist for applications to operate
  • Acceptance Criteria:
    • IaC templates are validated Resources created in target accounts Drift detection enabled Post-deploy health checks pass Rollback plan is defined and tested
• Initialize Database - (M): As a: Database administrator, I want to: initialize and seed the database schema, So that: an operational data store is available for applications
  • Acceptance Criteria:
    • Schema created in target database Seed data loaded Migrations tracked in version control Backup/restore policy defined and tested
• Configure Monitoring - (S): As a: SRE, I want to: configure monitoring and alerting for deployed services, So that: outages are detected and performance issues are alerted
  • Acceptance Criteria:
    • Monitoring dashboards show key metrics Alerts trigger for defined thresholds Logs are centralized and searchable Incident response runbook linked Monitoring configuration auditable

- [ ] Milestone 8: Ongoing maintenance, bug fixes, monitoring, user support and SLA processes

• Monitor System Health - (S): As a: system administrator, I want to: monitor system health and alert on anomalies, So that: I can ensure uptime and performance for users.
  • Acceptance Criteria:
    • System health dashboard shows key metrics (CPU, memory, disk, network) in real-time Alerts trigger when any predefined threshold is breached and include actionable details System logs are ingested and searchable for troubleshooting Edge case handling: monitor gracefully handles data gaps or sensor failures
• Performance Optimization - (M): As a: platform engineer, I want to: optimize performance hotspots and improve response times, So that: user experience remains fast during maintenance cycles.
  • Acceptance Criteria:
    • Baseline response time degrades < 10% under load Hotspot identified via profiling and optimized Caching/DB query improvements validated by benchmarks No regressions introduced in existing features
• Security Updates - (M): As a: security engineer, I want to: apply security updates and patch vulnerabilities, So that: systems remain protected against known threats.
  • Acceptance Criteria:
    • All critical and high-severity CVEs patched or mitigated Patching verified in staging before prod Backward-compatibility checks for plugins/modules Security scan reports show no critical vulnerabilities remaining
• Backup & Recovery - (L): As a: disaster recovery lead, I want to: implement reliable backup and restore procedures, So that: data can be recovered quickly after failure.
  • Acceptance Criteria:
    • Backups completed on schedule with integrity checks Restore process verified in a test environment RPO/RTO meet defined targets Offsite/offline backups tested for resilience
• Documentation Maintenance - (S): As a: knowledge manager, I want to: keep technical documentation up-to-date, So that: staff can find accurate guidance during maintenance and support.
  • Acceptance Criteria:
    • Documentation updated to reflect latest system changes Change logs generated for each update Documentation accessible via central repository and searchable User feedback loop established to identify outdated docs