The harness as the context manager

What this post added

This post details significant advancements in Glean's agent orchestration platform, focusing on context management and harness engineering. Key contributions include the implementation of Programmatic Tool Calling (PTC) within sandboxes to move workflow logic into code, enabling more robust and efficient execution of complex tasks. The introduction of sub-agents allows for the decomposition of agent loops into isolated execution contexts, improving scalability and reliability for large-scale analysis. Compaction strategies have been developed to preserve essential conversation state while offloading intermediate outputs to file systems, mitigating context window limitations. Furthermore, a search-first discovery mechanism for skills has been implemented, decoupling skill discovery from schema hydration and improving the agent's ability to select relevant capabilities efficiently.