TopCoder.App User Guide

Overview

TopCoder.App is a macOS desktop application that provides real-time AI assistance during technical interviews. It runs as an invisible overlay on your screen, completely undetectable by screen sharing, screen recording, and screenshot tools.

The app listens to your interviewer in real time, can capture and analyze any coding problem on screen, and generates solutions with exactly what to say, all without your interviewer seeing anything.

Installation

Stealth Verification

Before your first real interview, verify that TopCoder.App is truly invisible:

1. Open TopCoder.App so the overlay is visible on your screen.
2. Start a video call on Zoom, Google Meet, or any platform you use.
3. Share your entire screen.
4. Join the same call from your phone (or ask a friend to check).
5. Confirm the TopCoder overlay is completely invisible on the shared screen.

TopCoder uses proprietary stealth technology to be completely invisible to all screen capture tools at the operating system level. This means:

• Invisible to screen share on Zoom, Google Meet, Teams, Webex, and all other platforms
• Hidden from screen recordings and screenshots taken by other applications
• Not visible in Dock, Mission Control, Exposé, or Cmd+Tab
• Undetectable by monitoring or proctoring software

Your First Interview

1. Launch TopCoder.App before your interview starts. The overlay appears as two panels: a control strip at the top and an answer panel below it.
2. Start listening by pressing Cmd+M or clicking the microphone button. This captures both your microphone and system audio (your interviewer's voice).
3. Join your video call as you normally would. Share your screen if asked. TopCoder is invisible.
4. When a question comes up, you have two options:
   • Press Cmd+Shift+A to screenshot and analyze the visible code or problem
   • Press Cmd+J to ask for AI help based on the conversation transcript
5. Read the AI response on your overlay. It includes what to say, solution code, complexity analysis, and follow-up suggestions.
6. Minimize when not needed by pressing Cmd+Shift+Space. The app shrinks to a small dot in the corner, expandable with a click.

Screenshot Analysis

Screenshot analysis is TopCoder's most powerful feature. It captures your screen at double resolution and sends it to AI for vision-based analysis.

The AI response includes:

• Complete, runnable solution code in your preferred language
• Time and space complexity analysis
• A natural speaking script: what to say as you write the solution
• Clarifying questions to ask the interviewer (categorized as "need to ask" vs "nice to ask")
• Multiple solution approaches ranked by optimality

Live Transcription

TopCoder captures audio from two sources simultaneously:

• Your microphone: picks up what you say
• System audio: picks up your interviewer's voice from the video call

Audio is transcribed in real time using Deepgram's Nova-2 speech-to-text model. The transcript is displayed in an expandable panel and used as context when you ask for AI help, so the AI knows exactly what was discussed.

Auto-Detection

TopCoder continuously monitors the conversation and alerts you in three situations:

Alerts appear as a subtle pulsing indicator. Tap it or press Cmd+J to get AI help. There's a 10-second cooldown between alerts to avoid distraction.

Knowledge Base

The knowledge base lets you upload your own preparation materials (notes, cheat sheets, STAR stories, company research) so TopCoder can reference them during your interview and weave them into answers that sound like you.

Projects

Files are organized into projects. You might create one project per company or per interview type:

• Prepaid plans: up to 3 projects
• BYOK plans: unlimited projects

Supported File Types

File Limits

How It Works

When you upload a file, TopCoder breaks it into sections, generates vector embeddings, and stores them for fast similarity search. All plans include a built-in local vector database that runs entirely on your Mac with no cloud setup required. BYOK users can optionally connect Qdrant Cloud for higher capacity. During an interview, when you ask for help, TopCoder automatically searches your knowledge base for relevant content and includes it in the AI prompt, so the response incorporates your own notes, examples, and talking points.

Talk-Through Script

Every solution comes with a line-by-line explanation you can read right off the screen. Walk your interviewer through the logic like you wrote it yourself. The script covers:

• Why you chose this approach over alternatives
• Step-by-step walkthrough of the algorithm logic
• Time and space complexity justification
• Edge cases and how the code handles them

The script is written in natural conversational language — not code comments — so you can read it aloud naturally while walking through your solution. It's displayed alongside your code in the solutions view.

Solutions View

When TopCoder generates a solution for a coding problem, it presents multiple approaches in collapsible cards. Each approach includes:

You can navigate between responses using the up/down arrow keys and use quick actions like "Shorten", "Elaborate", "Try Again", or "Recap" to refine the output.

Keyboard Shortcuts

All shortcuts are global and work even when TopCoder is not the active window. Press Cmd+/ in the app to see this list.

Interview Types

Coding & Algorithm Interviews

TopCoder's primary strength. When you screenshot a coding problem from LeetCode, HackerRank, CoderPad, or any coding platform, it:

1. Identifies the problem type (arrays, trees, graphs, DP, etc.)
2. Generates multiple solution approaches ranked by optimality
3. Provides complete, runnable code in your preferred language
4. Includes time/space complexity analysis
5. Writes a speaking script for what to say as you code
6. Suggests clarifying questions to ask the interviewer
7. Generates a talk-through script for explaining your solution

Supported languages: Python, Java, C++, C#, JavaScript, TypeScript, Go, Kotlin, Swift, Rust, Ruby, PHP, Dart, Scala, Elixir, Erlang, and Racket. Set your preferred language in settings.

System Design Interviews

Upload your architecture notes, capacity estimation formulas, and design patterns to the knowledge base. During the interview, TopCoder:

• Pulls relevant notes from your knowledge base in real time
• Helps you articulate trade-offs between approaches
• Provides capacity estimates and back-of-the-envelope calculations
• Suggests follow-up points based on conversation context

Behavioral Interviews

Upload your STAR stories and talking points organized by competency. When the interviewer asks "Tell me about a time...", TopCoder searches your knowledge base and surfaces the most relevant story, structured in STAR format (Situation, Task, Action, Result).

Plans & Pricing

All plans include the same AI features: screenshot analysis, live transcription, auto-detection, knowledge base, and talk-through script. The only difference is the number of interview sessions.

Each interview session lasts up to 2 hours and supports up to 80 AI calls. One credit is consumed when you start a session.

BYOK Setup

BYOK (Bring Your Own Keys) is a one-time $150 purchase that gives you unlimited interviews forever. Instead of using TopCoder's API credits, you connect your own API keys and pay providers directly.

OpenAI — Required

Powers screenshot analysis, code solutions, and AI chat. This is the only key you must have.

1. Go to platform.openai.com and create an account.
2. Navigate to API Keys in the left sidebar.
3. Click Create new secret key, give it a name, and copy it.
4. Add a payment method under Billing (usage is typically a few cents per interview).
5. Paste the key into TopCoder's Settings panel in the desktop app.

Deepgram — Optional (for live transcription)

Enables real-time speech-to-text so TopCoder can hear your interviewer's questions. Without it, you can still use screenshot analysis and manual chat.

1. Go to console.deepgram.com and sign up (free tier includes $200 in credit).
2. Once in the dashboard, go to API Keys.
3. Click Create a New API Key, select all permissions, and copy it.
4. Paste the key into TopCoder's Settings panel.

Qdrant — Optional (for Knowledge Base)

Cloud-hosted vector search for the Knowledge Base. Without it, TopCoder uses a built-in local database — the Knowledge Base works either way. Qdrant Cloud is useful if you want faster search across larger document collections.

1. Go to qdrant.tech and create a free account.
2. Create a free 1 GB cluster in the Qdrant Cloud dashboard.
3. Copy the cluster URL and API key from the cluster details page.
4. Paste both into TopCoder's Settings panel.

BYOK Benefits

• Unlimited interview sessions (no credit deduction)
• 15 files per knowledge base project (vs 10 for prepaid)
• Unlimited file sizes and indexed content
• Optional Qdrant Cloud integration for higher-capacity vector search
• Direct API connections (lower latency)

Referrals

Share your referral code with friends to earn free interview credits. Here's how it works:

1. Find your unique referral code on the Referrals page of your dashboard.
2. Share it with friends who are preparing for interviews.
3. When they sign up and apply your code, they receive 1 free interview credit immediately.
4. When they make their first purchase (minimum $5), you earn referral credits.

Referral Rewards

Referral codes expire after 7 days but can be regenerated at any time from your dashboard.

Web Dashboard

The web dashboard at topcoder.app/dashboard lets you manage your account, purchase credits, and track usage.

Troubleshooting

Microphone or Screen Recording permission denied

Go to System Settings > Privacy & Security and enable TopCoder.App under both Microphone and Screen Recording. Restart the app after granting permissions.

Audio not being captured

Make sure listening is enabled (Cmd+M). If system audio isn't being captured, check that your video call's audio is playing through the default output device. TopCoder captures system audio using ScreenCaptureKit, which requires the Screen Recording permission.

App not invisible during screen share

This should not happen if the app launched correctly. Try quitting and relaunching TopCoder.App. If the issue persists, ensure you're running macOS 12 or later and that no accessibility tools are overriding window behavior.

Session expired or "No active session"

Each interview session has a 2-hour maximum duration. If your session expires mid-interview, start a new one (this consumes another credit for prepaid plans). BYOK plans have no session limits.

Credits not appearing after purchase

Credits are added automatically after Stripe confirms your payment. This usually takes a few seconds. Try refreshing your dashboard. If credits still don't appear after a few minutes, contact support@topcoder.app.

Knowledge base files not uploading

Check that your file is a supported type (PDF, DOCX, TXT, MD, RTF, PNG, JPG, HEIC) and within the size limit (2 MB for prepaid, unlimited for BYOK). Also verify you haven't exceeded the per-project file limit.