VS Code updates `git.addAICoAuthor`: false Copilot trailers force revert
VS Code briefly changed the `git.addAICoAuthor` default from `off` to `all`, then reverted after Copilot trailers appeared on non-AI commits and even when AI features were disabled. The incident matters because commit-history attribution is durable, so consent and runtime checks have to stay aligned with config defaults.
TL;DR
- the linked PR summary shows VS Code changed
git.addAICoAuthorfromofftoall, which made Copilot co-author trailers opt-out instead of opt-in. - According to the discussion summary, the rollout misfired badly enough to add trailers on non-AI commits and even when
chat.disableAIFeatureswas enabled. - HN commenters surfaced the implementation bug quickly: the schema default changed, but runtime behavior and AI-feature gating did not stay aligned.
- The rollback in Change default for
git.addAICoAuthorto off did two things at once: restored the default tooffand disabled AI contribution tracking when AI features are disabled, matching the complaint captured in the main HN thread.
VS Code's own 1.118 release notes framed the feature as default co-authoring for chat and agent workflows. The revert PR, Change default for git.addAICoAuthor to off, spells out the more interesting fix: schema default, runtime default, and AI-disable checks all had to move together. You can also compare that rollback with the current AI co-author attribution docs, which now list chatAndAgent as the default and note that the trailer is only added for commits made inside VS Code.
Default flip
VS Code PR #310226: Temporary Default Change for AI Co-Author Attribution
Pull Request #310226 in the VS Code repository was a temporary change that updated the default value of the git.addAICoAuthor setting from "off" to "all". This change, which was merged in April 2026, aimed to automatically add a Co-authored-by: Copilot trailer to commit messages when AI-generated code contributions were detected. Following the rollout, it was discovered that the feature contained a regression that incorrectly attributed non-AI code to Copilot, even when AI features were disabled. Consequently, the default was subsequently reverted to "off" in a follow-up PR (#313931).
The original change was tiny in diff size and large in blast radius. Enabling ai co author by default changed one setting, git.addAICoAuthor, from off to all.
That mattered because the official behavior split is concrete:
off: never add an AI co-author trailerchatAndAgent: add it for Copilot Chat or agent mode changesall: add it for all AI-generated code, including inline completions, per the current source control docs
VS Code's 1.118 release notes described the rollout as default Git AI co-authoring for chat and agent workflows. The PR evidence in the PR summary is broader, it says the default became all.
Revert patch
Discussion around VS Code inserting 'Co-Authored-by Copilot' into commits regardless of usage
Thread discussion highlights: - dmitriv on official apology and revert: Acknowledges the mistake of turning the feature on by default, says it should not be enabled when `disableAIFeatures` is on or when changes were not done by AI, and says the default will be reverted to off. - ddkto on regression in implementation: Points out that the schema default was changed but the runtime fallback still used `'off'`, making the intended default inconsistent and causing unexpected behavior. - srikanthsastry on consent and commit-history permanence: Argues the real issue is architectural: consent should be enforced down the stack, and commit history is permanent so you cannot simply undo the effect across repos.
The rollback was not just a default reset. In Change default for git.addAICoAuthor to off, VS Code also changed the runtime default to off, prevented AiContributionFeature from activating when AI features are disabled or hidden, and skipped trailer insertion when chat.disableAIFeatures is enabled.
That lines up with the two strongest complaints in the HN discussion summary: developers saw attribution on changes they said were not AI-generated, and one commenter pointed out that changing the schema default without matching runtime behavior created inconsistent behavior.
Commit history
VS Code inserting 'Co-Authored-by Copilot' into commits regardless of usage
The relevant takeaway is operational: VS Code briefly shipped an AI co-author attribution default that could leak into commit history even when AI was disabled or not involved, then had to be reverted. For engineers, this is a cautionary example about default settings, consent propagation, and test coverage for tooling that mutates source control metadata.
The sharpest objection was not branding. As the main HN thread notes, commit metadata is durable, and one highlighted comment argued consent has to be enforced lower in the stack because you cannot cleanly take attribution back once it lands across repos and forks.
The current staging and committing docs add one more boundary that was easy to miss during the backlash: the trailer is only added for commits made inside VS Code, not from external Git tools or the command line. That does not undo the bad default, but it does narrow where the mutation could happen.