Context Compounding Curve

Context Compounding Curve is the principle that an agency's agent stack gets cheaper per deliverable as shared memory accumulates, and more expensive per deliverable when each tool starts from zero. The first month of a retainer is the most expensive month: every agent re-learns the client's brand rules, stack constraints, and past decisions. By month six, a federated memory layer means a fact learned once (a rejected headline pattern, a CMS quirk, a compliance constraint) is recognized by every agent on the account. The curve bends only if memory is shared across tools rather than siloed per vendor. Bourdon's recognition-first federation and Vibsync's shared coding-agent memory both target that bend. The counterforce is model churn: Anthropic released Claude Sonnet 5.5 on September 28, 2026, cutting per-task costs up to 30 percent, which resets the tool layer but not the memory layer. Agencies that keep memory portable capture the savings; agencies that don't re-pay the learning cost on every model swap.