LangChain
A framework and platform for building applications with language models. Every Jev Daily story on LangChain, newest first. 5 stories since September 2026.
- Harrison Chase says Open SWE routing cut cost per task 64%
Model selection moved out of the agent and into the harness, with the quality bar as the gate.
- Chase splits trajectory labeling into typed answers in LangSmith
A shape for agent evals, posted without a cost or accuracy number attached.
- Harrison Chase says LangChain already ships Breunig's Jev router
The 15 minute sketch has a packaged equivalent, and Chase thinks the interesting version runs the router more than once.
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- GPT Researcher now runs on Jev by default
Assaf Elovic says the retrieval path no longer needs embeddings at all, on an eval his own team ran.
- LangChain tested Jev as a judge against LLM judges
The posts announce the comparison but publish none of the numbers, so the four axes are only as good as the write-up behind them.
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Jev, read daily so you do not have to. The builds, the benchmarks, the criteria that worked and the cases where it lost, from the people shipping on TypeSafe AI's System One model.