Harness 2: executing agent code as it streams (6 minute read)

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Summary

Framer's Harness 2 upgrades agent code execution by running JavaScript as it streams, cutting costs by up to 33% and speeding up execution by 20% while reducing tool steps and cached token usage significantly.

Framer's Harness 2 significantly upgrades the agent's execution process, allowing entire workflows in one program, achieving up to 33% cost reduction and 20% faster execution. This is done by executing JavaScript as it streams in, avoiding multiple model calls and using eager execution and early cancellation to enhance efficiency. The redesign also replaces DSL with method calls for real-time updates, making task execution streamlined for both in-app and external agents, reducing tool steps by 43% and cached input tokens by 39% per message.
Original Article

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