Rubber Duck Thursdays - Let's build with agents
In this episode, we recap the latest GitHub changelog updates including Copilot coding agent availability for pro users and the new Playwright MCP browser capability. We update Copilot custom instructions and setup steps for a GitHub Action project, use the Playwright MCP server to build interactive UI features on a trend radar app, and leverage Copilot coding agent to identify and fix technical debt.
Topics covered
- GitHub changelog recap — Copilot coding agent for Copilot Pro users, GitHub Actions fine-grain permissions, upgraded Llama models, improved PR file experience, Dependabot minimum package age configuration, and Copilot coding agent Playwright MCP browser support.
- Copilot custom instructions and setup steps — Updated custom instructions for a validate-file-exists GitHub Action project and created a Copilot setup steps YAML to configure the coding agent environment with Node.js and dependencies.
- Playwright MCP server for UI development — Used the Playwright MCP server with Copilot coding agent to build drag-and-drop functionality and point editing on a trend radar web app, demonstrating how the agent can interact with a running application.
- Technical debt with Copilot coding agent — Prompted Copilot to identify technical debt in the project, then created GitHub issues for package metadata fixes, documentation inconsistencies, and input validation improvements. Copilot coding agent autonomously submitted a PR addressing all three items with new tests.
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