An approved effect contract and a Claude Code MCP write enter a receipt gate that checks the principal, target, state change, and independent verification before completion

Require an effect receipt after every Claude Code MCP write

An MCP tool can return success after changing the wrong target or using the wrong authority. Make Claude Code prove the external effect before it reports completion.

August 1, 2026 · 5 min · 959 words · Thomas De Vos
Read Require an effect receipt after every Claude Code MCP write