7 min · +110 XP
When something breaks
Describe the symptom, paste the error, and know what to do when fixes do not help.
By the end of this lesson
You will be able to get a broken tool fixed and to break out of a loop of failed fixes.
Things will break: a button does nothing, the page looks wrong, a red error appears. This happens to professionals too. You do not have to find the cause yourself; you tell Claude what is wrong, in plain words.
Where to find the error
- 1In the terminal where Claude runs: select the red text, copy it and paste it into the prompt.
- 2In the browser, if the page looks broken but the terminal is quiet: press F12 (on a Mac in Chrome, Cmd+Option+J), open the Console tab and copy the red lines.
- 3No error anywhere? Describe it: "I clicked Save, the page blinked, and the list is empty." That is enough for Claude to start.
When fixes keep failing
Three steps, in this order
- 1Break the loop with the first phrase below.
- 2Start with a clean conversation in the same folder. Type /clear, then paste the second phrase. A conversation full of failed attempts often gets in the way more than the code does.
- 3Rebuild. Ask Claude to make a new folder and send an improved request that includes what you learned ("…and make sure Delete really removes the item"). If the old tool holds real data, move it over with the last two phrases.
“Stop. List three possible causes of this problem, try the simplest one first, and show me how you checked.”
Claude changes its approach instead of repeating the same fix.
“Read this folder and explain in plain words why the Delete button does not work. Then fix it and check that deleting works.”
A fresh look without the failed attempts in the way.
“Export all my data from this tool to a file and tell me where the file is.”
Do this in the old folder before you rebuild.
“Import my data from this file into the new version and check that everything is there: [path to the file].”
Do this in the new folder. Replace the part in brackets, or drag the file into the window.
›What /clear does
/clear starts a new conversation with an empty context in the same folder. Your files are not touched. The previous conversation is kept, and /resume can bring it back if you need it.
Once your tool holds data you would not want to lose, ask for an Export button with the phrase below. Use it from time to time. Then a broken version or a rebuild does not cost you your data.
“Add an Export button that saves all my data to a file, and an Import button that loads it back. Check both.”
Claude adds the two buttons and tests a round trip.
Give Claude the symptom, the likely location and what "fixed" looks like, and ask it to write a failing test that reproduces the issue before the fix. Ask it to address the root cause and not suppress the error. Point Claude at a log file instead of pasting it ("read @error.log and explain the error"), and use a subagent for a wide investigation so the main context stays clean. If Claude Code itself stops starting after you changed settings, hooks or plugins, claude --safe-mode starts it without them, so you can fix the config.
Claude has said "Fixed!" three times, and the button still does not work. What is the best next step?
Facts checked against the official Claude Code docs October 24, 2026 · source
Author
Evgenii Arsentev
PhD · Chief Executive Officer, digital health