# Using AI Coding Tools to Accelerate Test Coverage

DevFeed: [Using AI Coding Tools to Accelerate Test Coverage](<https://devfeed.tech/articles/pressure-to-change-21581.md>)

Original publisher: [Read original article](<https://maryrosecook.com/blog/post/pressure-to-change>)

Published: 2025-11-01T07:00:00Z

Content type: opinion

Language: en

Sources: [Mary Rose Cook](<https://devfeed.tech/sources/mary-rose-cook.md>)

Topics: [Testing](<https://devfeed.tech/topics/testing.md>), [Test coverage](<https://devfeed.tech/topics/coverage.md>), [codex](<https://devfeed.tech/topics/codex.md>), [Claude Code](<https://devfeed.tech/topics/claude-code.md>), [Claude](<https://devfeed.tech/topics/claude.md>)

Tags: [claude-code](<https://devfeed.tech/tags/claude-code.md>), [codex](<https://devfeed.tech/tags/codex.md>), [prompt](<https://devfeed.tech/tags/prompt.md>), [review](<https://devfeed.tech/tags/review.md>), [test-coverage](<https://devfeed.tech/tags/test-coverage.md>), [testing](<https://devfeed.tech/tags/testing.md>)

## AI overview

A Notion engineer reflects on using Claude Code guidance and Codex to speed up test writing during a time-limited test-coverage sprint. The author describes prompting Codex to prioritize important or complex functions and to carry a task from a function name through creating a pull request.

## Source excerpt

At Notion, we've been doing a quality sprint to increase our test coverage. Friday was the last day, and I wanted to get some more tests written. Time was short, which forced me to break my usual workflow. Not that I really have a usual workflow, these days. New AI-augmented programming tools and techniques come out every day. Everything is changing so fast that you can frequently become 10% more productive, forever, with a few minutes or a few hours invested. So, I push myself to try new things. But, inevitably, workflows are sticky. It's hard to change a habit. Extra cognitive load to monitor and refine the technique. Extra willpower to overcome the inertia of the familiar. Extra gumption to risk wasted time on something that isn't helpful. So I have my mega list of stuff to try and every few days I'll pluck something off it to try. But Friday was eye-opening. With time short, I wanted to get as much done as possible. And failure would mean only a few hours lost. We already had a bunch in place to speed things up. A Claude Code skill that my colleague, Jimmy, wrote. It laid out a careful, thorough process for writing tests. It included looking at our testing guide, tips on what to mock and an entreaty to look at surrounding test coverage. I pointed Codex at the Notion doc listing functions that needed coverage. I told it to find functions that are core parts of the system, or that have complex logic. This way, we could prioritize our time towards testing code that was important or gnarly. And, on Friday, here's the new stuff I tried - I'm rushing. Jimmy's skill is written for Claude, but I use Codex. What if I just point Codex at the skill directory in Claude's config? I'm rushing, so I have to get out of the loop. I need a process that can autonomously go from function name to PR. So I wrote a prompt with these steps: read the guidance on writing tests, write tests, create a branch, commit, review the code, refine the code, put up a PR. I'm rushing, so it's going