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Public story · 2026-02-23 · source-backed
Willison published a new guide entry in his systematized /guides/agentic-engineering-patterns/ section. Core insight: append "Use red/green TDD" to agent instructions. Every good model understands this as shorthand. The red phase is critical — "If you skip that step you risk building a test that passes already, hence failing to exercise and confirm your new implementation."
Key tip: explicitly ask agents to execute tests in their environment. Some models will not run code unless directed.
Source: Simon Willison
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Simon Willison released LLM / Shared entity: Simon Willison / Same source domain / Shared topic / What happened next
Linked by a graph relationship (Simon Willison released LLM); both cover Simon Willison; reported by the same outlet (simonwillison.net).
Linked by a graph relationship (Simon Willison released LLM); both cover Simon Willison; reported by the same outlet (simonwillison.net).
Linked by a graph relationship (Simon Willison released LLM); both cover Simon Willison; reported by the same outlet (simonwillison.net).