Option D fixes the actual failure while avoiding needless reprocessing. Anthropic’s Message Batches API treats every request independently, records the result against its unique custom_id, and explicitly states that one failed request does not affect the others. The 9,700 successful documents therefore require no retry. The failed requests exceeded the available context; increasing max_tokens changes the permitted output budget, not the size of the input context, so option C does not correct the cause. Resubmitting all 10,000 requests would repeat paid work, and prompt caching would only reduce some repeated-input cost without repairing oversized requests. Chunking each failed document reduces the input presented to Claude so every replacement request fits within the model’s context window . The application can then merge the extracted partial structures deterministically, retaining the original document identifier and chunk ordering. Anthropic recommends retry logic for failed batch requests and using custom_id to match results because batch results can arrive out of order. Consequently, selective retry plus chunking is both the technically correct recovery path and the lowest-cost option.

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