GitHub shipped three Copilot coding agent improvements on March 19: a 50% reduction in startup time for faster PR creation and iteration loops, a new semantic code search tool that finds relevant code by meaning rather than exact text match (2% faster task completion), and enhanced session logs showing repository cloning, agent firewall startup, and collapsible subagent activity. Jira integration for assigning issues to Copilot entered public preview on March 5.