Adversarial Dev Harness implements Anthropic pattern

The shift from single-agent chat to multi-agent adversarial harnesses is the defining trend for 2026 agentic engineering.

• –Moves beyond "vibe coding" by encoding a permanent "Reviewer" role that is incentivized to fail the "Builder."
• –Architecture prevents "context ceiling" issues by separating roles into distinct windows and using structured file-based communication.
• –Model-agnostic support for Claude Agent SDK and Codex SDK proves the pattern's portability.
• –Uses a "Contract Negotiation" phase where agents agree on success criteria before a single line of code is written.
• –Built on the Bun runtime for performance, signaling a trend towards high-speed, local-first agent execution.