Coding Agents Need a Faster Feedback Loop

The Foundation of Autonomous Coding

That means linting, formatting, and tests must run locally and complete quickly. If a single test run takes minutes, the agent can’t safely explore or validate changes. The faster the loop, the smarter and safer the agent becomes.

Speed isn’t a luxury here — it’s the foundation for autonomous coding to work.

Why This Matters More for Agents Than Humans

Humans can context-switch while tests run. We check email, review a PR, grab coffee. An AI agent doesn’t have that luxury. It’s sitting there, burning tokens and time, waiting for a result before it can take the next step. A five-minute test suite means five minutes of dead time per iteration. Over a complex feature with dozens of iterations, that adds up to hours of wasted compute.

But there’s a deeper problem. Agents make mistakes. That’s expected and fine — as long as they can detect and correct those mistakes quickly. A fast feedback loop means the agent catches a broken test within seconds, fixes it, and moves on. A slow feedback loop means the agent has already written three more files on top of a broken foundation before it discovers anything went wrong.

What Fast Looks Like

For effective agent-driven development, aim for these targets:

• Linting: Under 5 seconds for the changed files
• Formatting: Under 2 seconds
• Unit tests: Under 30 seconds for the relevant test files
• Type checking: Under 10 seconds for incremental checks

If your full test suite takes 10 minutes, that’s fine for CI. But you need a way for the agent to run just the relevant tests in seconds. Tools like test file matching, watch mode, and incremental compilation make this possible.

The Investment Pays Off

Every minute you spend optimizing your local feedback loop doesn’t just help you — it helps every agent session that follows. A fast test suite is a force multiplier. It makes your agents braver, because they can afford to experiment. It makes them safer, because they catch problems early. And it makes them faster, because they spend less time waiting and more time building.

If you’re investing in AI-assisted development, invest in your feedback loop first. Everything else depends on it.

This article was originally posted on LinkedIn.