The Hallway Track
Product Launches

Introducing: LangSmith Tuned Evaluators

LangChain · Aug 18, 2026 · Product Launches

LangChain launches tuned evaluators that beat frontier models on agent evals at lower cost

“our post-trained perceived error evaluator outperformed all frontier closed and open models, while still remaining the most cost-effective”

LangChain launched LangSmith Tuned Evaluators, specialized models managed end-to-end by LangChain that claim to outperform frontier models on specific evaluation tasks at a fraction of the cost. The first evaluator, 'Perceived Error,' detects agent failures in multi-turn conversations by spotting subtle signals like contradictory answers and unresolved outcomes — no custom prompts or inference infrastructure required. This matters because most production AI failures don't surface as system errors and users rarely leave explicit ratings, making scalable automated quality signal a critical gap for agent teams.

LangChain LangSmith agent-evaluation observability cost-efficiency

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