Why This Matters

Inline completions are the most-used Copilot surface. Knowing the keyboard shortcuts fluidly turns Copilot from a curiosity into a tool you reach for every minute.

Concept Explained

Inline completions appear as gray ghost text after you pause typing. The model watches your cursor and the surrounding lines, predicts what comes next, and renders the prediction inline. You accept, reject, or cycle alternatives.

How It Works

VS Code listens to text-changed events, debounces for the configured delay (~400ms default), sends context to the Copilot service, and renders the returned tokens as ghost text. Pressing Tab merges the ghost text into your buffer. Cycling asks the service for alternative completions.

Step-by-Step Tutorial

1. Trigger a completion

2. Accept with Tab

3. Reject with Esc

4. Cycle alternatives

5. Force-trigger

Real-World Example

A backend dev writing a TypeScript Express handler typed the function signature and paused. Copilot proposed a complete handler with error handling, validation, and a typed response. The dev accepted the body, modified the validation rules to match their schema, and shipped in 90 seconds. Without Copilot, the same handler would have taken 5 minutes.

Example Prompts / Commands / Code

// Type this signature and pause:
function parseDate(input: string): Date | null {
  // Copilot proposes:
  //   const d = new Date(input);
  //   return isNaN(d.getTime()) ? null : d;
}

Tab                 accept full suggestion
Ctrl+Right          accept one word
Esc                dismiss
Alt+]  (Opt+])     next alternative
Alt+[  (Opt+[)     previous alternative
Alt+\  (Opt+\)     force trigger

Common Mistakes

• Tab-Tab-Tab without reading — biggest source of Copilot bugs.
• Forgetting Esc exists — dismissing bad suggestions is as important as accepting good ones.
• Never cycling alternatives — the first suggestion isn't always best.
• Forcing triggers constantly — uses more credits, rarely helps.

Best Practices

• Read every suggestion before accepting.
• Cycle alternatives when the first suggestion feels off.
• Accept word-by-word for long suggestions to keep control.
• Adjust the delay in settings to match your typing speed.

Troubleshooting

Practical Exercise

Frequently Asked Questions

Further Reading

• Getting code suggestions in your IDE

Official References

• Getting code suggestions

Related lessons: BE-08, BE-13