Build your own AI harness: Claude Agent SDK tutorial for GTM workflows

The Gist

• Lenny builds a Sentry bug-debugging harness using Claude Agent SDK and GPT-5.5
• Harness handles evidence gathering, root-cause analysis, and follow-up artifact creation
• Architecture includes runs, tasks, tools, and artifacts for structured workflows
• Full code walkthrough available on YouTube, Spotify, and Apple Podcasts

• An AI harness is a structured system that automates repetitive workflows by integrating AI models with specific tools and permissions.
• Building a harness is preferable to using general-purpose AI tools when dealing with structured, repetitive tasks requiring specific permissions and outputs.
• The Claude Agent SDK can be used to create custom harnesses that handle evidence gathering, root-cause analysis, and artifact creation.
• Every harness needs three components: runs, tasks, and artifacts, structured to ensure usability by the entire team.
• GPT-5.5 and Claude Opus were used to build the harness code, demonstrating the potential of AI in developing AI tools.
• A well-structured harness can eliminate the need for repetitive manual inputs, such as typing prompts for each task.

• Identify repetitive, structured workflows in your business that could benefit from automation via an AI harness.
• Use the Claude Agent SDK to build custom harnesses, integrating with tools like Sentry, Linear, GitHub, and Vercel for specific tasks.
• Structure the output artifacts of your harness to ensure they are usable by the entire team, not just the AI.
• Experiment with AI models like GPT-5.5 and Claude Opus to assist in the development of your harness code.