Ask a coding agent to fix an existing PR
Uh oh! Task: Uh oh! There was an error while loading. Please reload this page. bgrainger Feb 26, 2026 Select Topic Area Bug Copilot Feature Area Copilot Coding Agent Body Step 1: Open a PR on a repo. Copilot posts the message: Mention @copilot in a comment to make changes to this pull request. Step 2: Follow those instructions and mention Copilot, asking it to make a fix to the PR: Expected Outcome: Copilot pushes changes to the existing PR, fixing the code in place. Actual Outcome: Copilot opens a new PR. I don't want a new PR and then have to merge changes into my initial PR. I want Copilot to be able to push small fixes, the way a human coworker would. Example: Faithlife/FaithlifeBuild#81 Replies: 5 comments · 4 replies Uh oh! There was an error while loading. Please reload this page. github-actions[bot] Bot Feb 26, 2026 💬 Your Product Feedback Has Been Submitted 🎉 Thank you for taking the time to share your insights with us! Your feedback is invaluable as we build a better GitHub experience for all our users. Here's what you can expect moving forward ⏩ Your input will be carefully reviewed and cataloged by members of our product teams. Due to the high volume of submissions, we may not always be able to provide individual responses. Rest assured, your feedback will help chart our course for product improvements. Due to the high volume of submissions, we may not always be able to provide individual responses. Rest assured, your feedback will help chart our course for product improvements. Other users may engage with your post, sharing their own perspectives or experiences. GitHub staff may reach out for further clarification or insight. We may 'Answer' your discussion if there is a current solution, workaround, or roadmap/changelog post related to the feedback. We may 'Answer' your discussion if there is a current solution, workaround, or roadmap/changelog post related to the feedback. Where to look to see what's shipping 👀 Read the Changelog for real-time updates on the latest GitHub features, enhancements, and calls for feedback. Explore our Product Roadmap, which details upcoming major releases and initiatives. What you can do in the meantime 💻 Upvote and comment on other user feedback Discussions that resonate with you. Add more information at any point! Useful details include: use cases, relevant labels, desired outcomes, and any accompanying screenshots. As a member of the GitHub community, your participation is essential. While we can't promise that every suggestion will be implemented, we want to emphasize that your feedback is instrumental in guiding our decisions and priorities. Thank you once again for your contribution to making GitHub even better! We're grateful for your ongoing support and collaboration in shaping the future of our platform. ⭐ Uh oh! There was an error while loading. Please reload this page. bgrainger Feb 26, 2026 Author I can sort of understand not allowing Developer B to request Copilot to push changes to Developer A's PR without permission, but if the initial developer requests a change on their own PR, it should succeed. (OTOH, if Developer B already has permission to push to Developer A's branch, Copilot should be able to act on Developer B's behalf to push changes.) Uh oh! There was an error while loading. Please reload this page. bgrainger Mar 24, 2026 Author At https://devblogs.microsoft.com/dotnet/ten-months-with-cca-in-dotnet-runtime/, @stephentoub writes: Many of those interventions are for things that CCA would actually be quite good at, and I expect we would make significantly more use of CCA in dotnet/runtime if we were able to summon it for assistance on PRs it didn’t create. Unfortunately, at the moment, CCA is unable to assist with PRs where the source branch is not in the same repo, which is the case for pretty much every human-authored PR in dotnet/runtime (the PRs come from branches in forks). The day CCA gains that capability will be a huge boon for productivity of dotnet/runtime maintainers. My guess is that the core issue is the one in my original post: Copilot can't edit PRs it didn't create. (Most PRs from forks enable the ability for maintainers to push changes, so if that default setting were enabled and if Copilot were considered a "maintainer" it should also be able to push to branches on forks.) Uh oh! There was an error while loading. Please reload this page. My guess was wrong: https://github.com/orgs/community/discussions/188127#discussioncomment-16309826; tools: GitHub Copilot. Human role: The original post does not say how a person stayed involved.; limitations: Prerequisites include a GitHub repository with Copilot enabled and a PR created by a human. A major constraint is that the agent cannot currently modify PRs originating from forks, limiting its utility for open-source or cross-repo workflows. Integration uncertainty remains regarding whether the agent will respect branch permissions or always create new branches. Human approval is necessary to review any code changes before merging..
Tools
Published on Agent Work Atlas:
Overview
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Workflow
Uh oh! There was an error while loading. Please reload this page. bgrainger Feb 26, 2026 Select Topic Area Bug Copilot Feature Area Copilot Coding Agent Body Step 1: Open a PR on a repo. Copilot posts the message: Mention @copilot in a comment to make changes to this pull request. Step 2: Follow those instructions and mention Copilot, asking it to make a fix to the PR: Expected Outcome: Copilot pushes changes to the existing PR, fixing the code in place. Actual Outcome: Copilot opens a new PR. I don't want a new PR and then have to merge changes into my initial PR. I want Copilot to be able to push small fixes, the way a human coworker would. Example: Faithlife/FaithlifeBuild#81 Replies: 5 comments · 4 replies Uh oh! There was an error while loading. Please reload this page. github-actions[bot] Bot Feb 26, 2026 💬 Your Product Feedback Has Been Submitted 🎉 Thank you for taking the time to share your insights with us! Your feedback is invaluable as we build a better GitHub experience for all our users. Here's what you can expect moving forward ⏩ Your input will be carefully reviewed and cataloged by members of our product teams. Due to the high volume of submissions, we may not always be able to provide individual responses. Rest assured, your feedback will help chart our course for product improvements. Due to the high volume of submissions, we may not always be able to provide individual responses. Rest assured, your feedback will help chart our course for product improvements. Other users may engage with your post, sharing their own perspectives or experiences. GitHub staff may reach out for further clarification or insight. We may 'Answer' your discussion if there is a current solution, workaround, or roadmap/changelog post related to the feedback. We may 'Answer' your discussion if there is a current solution, workaround, or roadmap/changelog post related to the feedback. Where to look to see what's shipping 👀 Read the Changelog for real-time updates on the latest GitHub features, enhancements, and calls for feedback. Explore our Product Roadmap, which details upcoming major releases and initiatives. What you can do in the meantime 💻 Upvote and comment on other user feedback Discussions that resonate with you. Add more information at any point! Useful details include: use cases, relevant labels, desired outcomes, and any accompanying screenshots. As a member of the GitHub community, your participation is essential. While we can't promise that every suggestion will be implemented, we want to emphasize that your feedback is instrumental in guiding our decisions and priorities. Thank you once again for your contribution to making GitHub even better! We're grateful for your ongoing support and collaboration in shaping the future of our platform. ⭐ Uh oh! There was an error while loading. Please reload this page. bgrainger Feb 26, 2026 Author I can sort of understand not allowing Developer B to request Copilot to push changes to Developer A's PR without permission, but if the initial developer requests a change on their own PR, it should succeed. (OTOH, if Developer B already has permission to push to Developer A's branch, Copilot should be able to act on Developer B's behalf to push changes.) Uh oh! There was an error while loading. Please reload this page. bgrainger Mar 24, 2026 Author At https://devblogs.microsoft.com/dotnet/ten-months-with-cca-in-dotnet-runtime/, @stephentoub writes: Many of those interventions are for things that CCA would actually be quite good at, and I expect we would make significantly more use of CCA in dotnet/runtime if we were able to summon it for assistance on PRs it didn’t create. Unfortunately, at the moment, CCA is unable to assist with PRs where the source branch is not in the same repo, which is the case for pretty much every human-authored PR in dotnet/runtime (the PRs come from branches in forks). The day CCA gains that capability will be a huge boon for productivity of dotnet/runtime maintainers. My guess is that the core issue is the one in my original post: Copilot can't edit PRs it didn't create. (Most PRs from forks enable the ability for maintainers to push changes, so if that default setting were enabled and if Copilot were considered a "maintainer" it should also be able to push to branches on forks.) Uh oh! There was an error while loading. Please reload this page. My guess was wrong: https://github.com/orgs/community/discussions/188127#discussioncomment-16309826
Reported result
The expected outcome of in-place fixes was not achieved; instead, Copilot opened a new PR, forcing the user to manually merge changes back into the initial PR. Furthermore, the feature does not work for PRs where the source branch is in a fork, which represents the majority of human-authored PRs in many projects. No successful automated fix was reported for the original PR.
Human role
The original post does not say how a person stayed involved.
Limitations
Prerequisites include a GitHub repository with Copilot enabled and a PR created by a human. A major constraint is that the agent cannot currently modify PRs originating from forks, limiting its utility for open-source or cross-repo workflows. Integration uncertainty remains regarding whether the agent will respect branch permissions or always create new branches. Human approval is necessary to review any code changes before merging.
Try it
Act as a GitHub Copilot Coding Agent. I have a PR [replaceable PR URL] in repo [replaceable repo name] where I need a small fix for [replaceable bug description]. Steps: 1. Check if the PR source branch is in the same repo or a fork. If it's a fork, stop and report that in-place editing is unsupported. 2. If same-repo, analyze the code in [replaceable file path] and propose a fix for [replaceable bug description]. 3. Do NOT push changes yet. Show me the diff and the commit message you intend to use. 4. Wait for my explicit confirmation. 5. Upon confirmation, attempt to push the commit to the existing PR branch. If the system forces a new PR, stop and report the failure. Deliverables: A diff preview, a commit message, and a status report on whether the push succeeded or failed. Quality Check: The fix must resolve [replaceable bug description] without breaking existing tests. If inputs are missing, ask for the specific file and error log. Do not publish or merge anything without my approval.
Source reports are not independently verified. Publication date is the catalog publication date, not the original article date.