Amp Tab by Sourcegraph — intent‑aware “Tab” that edits across files (now on by default)

Joel Horwitz — Wed, 24 Sep 2025 17:28:51 +0000

TL;DR — Amp Tab is Amp’s new in‑editor completion engine. It watches your recent changes, IDE diagnostics, and semantic context to suggest multi‑line (and even cross‑file) edits you can accept with Tab. It’s free and, as of Sept 23, 2025, it’s on by default for new installs of the Amp extension.

What is Amp Tab?

Amp Tab is a smart completion engine that goes beyond ordinary autocomplete. Instead of just filling in the next token, it predicts the next meaningful edit you’re likely to make—using your recent edits, the language server’s diagnostics, and Amp’s notion of semantic context. Suggestions can be single- or multi‑line and may apply near your cursor or elsewhere in the file.

Since launch, Amp Tab has grown to handle edits across multiple files too—so if an accepted change introduces an error, Tab can propose the follow‑up edits required to get your project back to green.

What’s new right now

On by default for new installs (Sept 23, 2025). If you install the Amp extension today, Amp Tab is enabled automatically. Already installed Amp? Run “Enable Amp Tab” from the Command Palette (Cmd/Ctrl + Shift + P). Works in VS Code, Windsurf, and Cursor.
30% faster (and up to 50% faster at peak). The team reworked the serving stack with Baseten, moved to TensorRT‑LLM, and added KV caching plus speculative/lookahead decoding tweaks—cutting latency significantly.
Multi‑file Tab flow. Press Tab to preview the suggested target file, then Tab again to jump and apply the edit—especially handy when a change in one module breaks imports or types in another.

How to turn it on (if you already use Amp)

If you installed Amp before the default roll‑out:

Open the Command Palette and run Enable Amp Tab.
Or add this setting in your editor config:

{
  "amp.tab.enabled": true
}

Tip: If you use a Vim extension in VS Code and need Esc to both dismiss suggestions and return to normal mode, configure amp.tab.dismissCommandIds (defaults cover VSCodeVim and vscode‑neovim).

How it feels in practice

Here’s a common loop Amp Tab smooths out:

You rename a function or reshape a type.
Diagnostics light up elsewhere.
Amp Tab proactively suggests the follow‑on edits—in the same file or other recently viewed files.
Press Tab to apply, Tab again to jump to the next fix, or keep typing to ignore.

Because suggestions are powered by semantic context plus your IDE’s diagnostics, they often feel like the edit you were about to make—just a few keystrokes earlier.

Supported editors

VS Code, Windsurf, and Cursor (Amp extension).

Why this is different from “regular autocomplete”

Traditional autocomplete guesses the next tokens near the cursor. Amp Tab aims at the intent of your next change, which may require multi‑line updates or coordinated edits elsewhere—especially after refactors. That’s a subtle but impactful shift from token prediction to change prediction.

Performance notes for the curious

Under the hood, the team reports a 30% average latency reduction (and up to 50% at peak) thanks to: a new deployment with Baseten, TensorRT‑LLM inference, KV caching, and a modified lookahead decoding strategy with improved n‑gram candidate selection and variable‑length speculations—reducing both draft tokens and per‑iteration compute.

Pricing & availability

Amp Tab is free today and originally launched as a research preview available to all Amp users. With the latest update it’s now on by default for new installs, so the easiest path is simply to install the Amp extension and start typing.

Quick start checklist

[ ] Install Amp and open your project. (Amp is built by Sourcegraph.)
[ ] If you’re an existing user, run Enable Amp Tab or set "amp.tab.enabled": true.
[ ] Start typing; press Tab to accept edits, Tab again to jump to the next or to a related file.
[ ] Optional: tune Vim dismissal with amp.tab.dismissCommandIds.

Sources & further reading

Amp News & blog — https://www.ampcode.com/news
Amp by Sourcegraph YouTube channel — https://www.youtube.com/@Sourcegraph

If you’ve tried Amp Tab already, I’d love to hear how it changes your refactor and fix‑up loops—especially in larger codebases. What did it help you skip?

Forem: Joel Horwitz