Artificial Analysis releases Endpoint Accuracy Index v1.1 with tighter long-context intervals and six-model coverage

Artificial Analysis launched Endpoint Accuracy Index v1.1, which tightens AA-LCR-25 confidence intervals and adds coverage for GLM-5.3 Flash and Muse Spark Open. Across 103 serverless endpoints benchmarked, 24 score statistically below the self-hosted reference, with causes including output token caps, reduced reasoning, tool call formatting errors and request timeouts. Raising AA-LCR-25 to 25 repeats per question narrows its average 95% confidence interval from ±4.7 to ±2.6 points, and the composite index interval from ±5.5 to ±4.3 points across the 45 endpoints scored under both versions.