What Will Replace Pull Requests? Rethinking Software Collaboration for AI Agents

The emergence of artificial intelligence (AI) coding agents has put pull requests under pressure: agents open millions of pull requests per month, while some open-source projects have begun to restrict or disable external contributions. We investigate which alternatives to pull requests practitioners are proposing or adopting and what these changes mean for empirical software engineering research. We reviewed 50 gray-literature documents from 31 organizations or individuals published between October 2025 and October 2026, coding the problems each named, the mechanisms it proposed or adopted, which of five roles of pull requests (integration, review, rationale, accountability, and external contribution) each mechanism takes over, and the evidence offered. Most responses retained pull requests in some form, whether by adding tooling, attaching a new artifact, or restricting access, and restriction was the response most often reported as adopted. Several proposed alternatives moved review and rationale into agent conversations and session records, but only Zed reported using a replacement in practice. Only two documents outlined a replacement for external contribution, and neither reported adoption. Pull requests are changing in ways that pull-request datasets will not capture: reviews conducted in agent conversations leave no pull-request comments, and projects that disable pull requests disappear from samples of newly opened ones. We outline a research agenda on the effectiveness of the emerging alternatives, their consequences for open-source participation, and the adaptation of empirical methods.