Choose a coding agent harness, model, and task dataset and optimize context and prompts to get the best performance for long-horizon tasks
Synth is a Y Combinator company in the Fall 2024 batch. Its directory entry describes it as: Prompt and Context Optimization for Coding Agents. The founder listed is Josh Purtell (Founder/CEO) (Y Combinator directory entry, October 15, 2024).
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New accelerator entry · 2024-10-15 · the record
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Choose a coding agent harness, model, and task dataset and optimize context and prompts to get the best performance for long-horizon tasks
Most-starred repository: synth-ai — 82 stars, Python.
Counted 2026-09-27 across repositories the account owns; forks are excluded.
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Increase your Experiments Per Minute with Synth Workshop. Local first-class, API first-class research on your Mac.
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Josh is the founder and CEO of Synth. Before Synth, Josh was employee #3 and research scientist at Basis, which uses AI agents to automate accounting tasks. Previously, he built out the ML core of a Cyber Threat Intelligence SaaS product at Halborn, a cyber security startup that acqui-hired his startup Politeia. He founded Politeia while wrapping up a Math undergrad at Yale, where he did time-series ml research for fun.
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