Once AI coding agents reach a high performance level, objective benchmarks become less important than a developer's subjective experience. Like a warrior choosing a sword, the best tool is often the one that has the right "feel," writes code in a preferred style, and integrates seamlessly into a human workflow.

Block's CTO quantifies the impact of their internal AI agent, Goose. AI-forward engineering teams save 8-10 hours weekly, a figure he considers the absolute baseline. He notes, "this is the worst it will ever be," suggesting exponential gains are coming.

AI's impact on coding is unfolding in stages. Phase 1 was autocomplete (Copilot). We're now in Phase 2, defined by interactive agents where developers orchestrate tasks with prompts. Phase 3 will be true automation, where agents independently handle complete, albeit simpler, development workflows without direct human guidance.

The most significant productivity gains come from applying AI to every stage of development, including research, planning, product marketing, and status updates. Limiting AI to just code generation misses the larger opportunity to automate the entire engineering process.

Increased developer productivity from AI won't lead to fewer jobs. Instead, it mirrors the Jevons paradox seen with electricity: as building software becomes cheaper and faster, the demand for it will dramatically increase. This boosts investment in new projects and ultimately grows the entire software engineering industry.

Contrary to the idea that AI will eliminate the need to code, it's making coding a crucial skill for non-technical roles. AI assistants lower the barrier, allowing professionals in marketing or recruiting to build simple tools and automate tasks, giving them a significant advantage over non-coding peers.

The value generated by 30 million developers worldwide is estimated at $3 trillion. AI tools that augment or disrupt this work are tapping into a market equivalent to the GDP of a major economy, making it the first truly massive market for AI.

An emerging power-user pattern, especially among new grads, is to trust AI coding assistants like Codex with entire features, not just small snippets. This "full YOLO mode" approach, while sometimes failing, often "one-shots" complex tasks, forcing a recalibration of how developers should leverage AI for maximum effectiveness.

As AI generates more code, the core engineering task evolves from writing to reviewing. Developers will spend significantly more time evaluating AI-generated code for correctness, style, and reliability, fundamentally changing daily workflows and skill requirements.