Fix a failing build: how to do it with AI
Last checked 2026-10-15
AdvancedBot with human review 💻 Coding
Agent reads errors, edits code and re-runs until green.
1. Bot automation level
Bot with human review Agents act on real systems; review plans, approvals and results before trusting them.
2. Before you hand it to the bot
- Gather inputs: files, data samples, links and any templates.
- Set up access: connect only the apps/repos the agent needs, with least-privilege accounts.
- Context: tell the bot audience, purpose, constraints and examples of good output.
- Privacy check: remove personal, confidential or regulated data unless your plan/workspace is approved for it.
- Success criteria: write down what 'done' looks like (length, format, tests passing, fields filled).
3. Copy-paste prompts
Main prompt
CI is failing on main (log below). Reproduce it, explain the root cause, then make the minimal fix on a new branch, re-run the tests and open a PR. Do not disable or skip tests. <log>
Beginner-friendly
CI is failing on main (log below). Reproduce it, explain the root cause, then make the minimal fix on a new branch, re-run the tests and open a PR. Do not disable or skip tests. <log> I'm new to this: explain each step in plain words and ask me for anything you need before starting.
Check-your-work
CI is failing on main (log below). Reproduce it, explain the root cause, then make the minimal fix on a new branch, re-run the tests and open a PR. Do not disable or skip tests. <log> When you finish, list any assumptions you made, anything you're unsure about, and what I should double-check before using the result.
Free tiers that can handle this (verified): GitHub Copilot, ChatGPT (incl. Work & Codex). Others: check plan.
4. Step-by-step
- Copy the failing CI log URL or output.
- Give a cloud/IDE agent repo access (Copilot cloud agent via an issue, Cursor Cloud Agent, Claude Code, Codex cloud).
- Ask it to reproduce the failure locally first and explain the root cause before editing.
- Let it make the smallest fix on a new branch and re-run the failing job/tests.
- Review the diff yourself; check it didn't skip or delete tests.
- Merge only after CI passes and a human approves.
5. Which bots and plans can do it
| Tool | What's different here | Plan limits | Source |
|---|---|---|---|
| Cursor | Cloud Agents run in isolated VMs and can attach logs/screenshots to the PR. | Pricing page unverified; cloud agents require a connected source-control repo. | cursor.com/docs/agent/overview |
| GitHub Copilot | Cloud agent runs in a GitHub Actions environment: one repo, one branch, one PR per task. | Free: 2,000 completions + 50 chats; cloud agent listed on paid plans. | docs.github.com/en/copilot/concepts/agents/cloud-agent/about-cloud-agent |
| Claude (incl. Claude Code) | Claude Code also runs in GitHub Actions/GitLab CI. | Claude Code and Research need Pro or higher; computer use is Pro/Max only (research preview). | code.claude.com/docs/en/desktop |
| ChatGPT (incl. Work & Codex) | Codex can work in cloud environments and review PRs. | Free tier has limited deep research, Codex and Work; scheduled tasks need Go or higher (per chatgpt.com/pricing). | help.openai.com/en/articles/20001275-chatgpt-work-and-codex |
Free or paid?
- Cursor: Free: not verified, so check the official site. Paid: price not verified, so check the official site. For this task, check the plan.
- GitHub Copilot: Free plan: yes. 2,000 completions and 50 chat requests a month; agent mode and CLI. Paid: the lowest price we could verify on the official pricing page is $10/month (other plans may exist). Its free tier can handle this task.
- Claude (incl. Claude Code): Free plan: yes. chat, web search, files & code execution, Artifacts, connectors. Claude Code and Research need Pro. Paid: the lowest price we could verify on the official pricing page is $20/month (other plans may exist). For this task, check the plan.
- ChatGPT (incl. Work & Codex): Free plan: yes. unlimited text chats; limited uploads, images, voice, deep research and Codex. Paid: price not verified, so check the official site. Its free tier can handle this task.
6. Risks and what to double-check
- Agents may 'fix' builds by disabling tests or loosening checks — inspect the diff.
- Grant only the repo and secrets needed; cloud agents run with network access you configure.
- Run tests and review diffs; never merge unreviewed agent code.
- AI can hallucinate facts — verify anything that matters.
- Watch for prompt injection from web pages, emails or files the agent reads.
Professions that use this
Software developer · DevOps / SRE engineer