{"@context":"https://neupai.io/schema/v0.2","@type":"StructuredNewsArticle","identity":{"article_id":"tech42_20260423_anthropic-claude-performance-degradation","canonical_url":"https://www.tech42.co.kr/%ec%9d%98%eb%8f%84%ec%a0%81-%ec%84%b1%eb%8a%a5-%ec%a0%80%ed%95%98-%ec%95%84%eb%8b%88%ec%97%88%eb%8b%a4%ec%95%a4%ed%8a%b8%eb%a1%9c%ed%94%bd-%ed%81%b4%eb%a1%9c%eb%93%9c-%ec%84%b1%eb%8a%a5/?utm_source=rss&utm_medium=rss&utm_campaign=%25ec%259d%2598%25eb%258f%2584%25ec%25a0%2581-%25ec%2584%25b1%25eb%258a%25a5-%25ec%25a0%2580%25ed%2595%2598-%25ec%2595%2584%25eb%258b%2588%25ec%2597%2588%25eb%258b%25a4%25ec%2595%25a4%25ed%258a%25b8%25eb%25a1%259c%25ed%2594%25bd-%25ed%2581%25b4%25eb%25a1%259c%25eb%2593%259c-%25ec%2584%25b1%25eb%258a%25a5","ai_url":null,"publisher":{"name":"테크42","domain":"www.tech42.co.kr","type":"online"},"author":"버트","published_at":"2026-04-23T22:53:04.000Z","updated_at":null,"language":"en","article_type":"straight_news","originality":"self_produced"},"content":{"headline":"\"It wasn't intentional performance degradation\"...Anthropic reveals 3 causes of Claude performance decline","summary":"Anthropic released an official post-mortem analysis report identifying three product layer changes as the causes of Claude code's performance degradation. The company revealed that reduced reasoning effort levels, prompt caching bugs, and system prompt brevity instructions were the causes.","topics":["ai","software"],"geography":["US"],"entities":[{"name":"Anthropic","canonical_id":"corp:us:anthropic","type":"company","role_in_article":"primary_subject","metadata":{"ticker":null,"parent":null}},{"name":"Claude","canonical_id":"product:us:claude","type":"product","role_in_article":"primary_subject","metadata":{"ticker":null,"parent":null}},{"name":"Stella Lorenzo","canonical_id":"person:us:stella-lorenzo","type":"person","role_in_article":"source","metadata":{"ticker":null,"parent":null}},{"name":"AMD AI Group","canonical_id":"org:us:amd-ai-group","type":"organization","role_in_article":"source","metadata":{"ticker":null,"parent":null}}],"claims":[{"id":"c1","statement":"On March 4, the default reasoning effort level was downgraded from 'high' to 'medium'","as_of":"2026-03-04","as_of_explicit":true,"as_of_raw":"March 4","source_type":"company_disclosure","comparison":null,"type":"fact","figures":null,"expiry_hint":null,"insight":null},{"id":"c2","statement":"On April 7, Opus 4.7 default was restored to 'xhigh'","as_of":"2026-04-07","as_of_explicit":true,"as_of_raw":"April 7","source_type":"company_disclosure","comparison":null,"type":"fact","figures":null,"expiry_hint":null,"insight":null},{"id":"c3","statement":"On March 26, a prompt caching optimization bug was deployed","as_of":"2026-03-26","as_of_explicit":true,"as_of_raw":"March 26","source_type":"company_disclosure","comparison":null,"type":"fact","figures":null,"expiry_hint":null,"insight":null},{"id":"c4","statement":"On April 10, the prompt caching bug was fixed in version v2.1.101","as_of":"2026-04-10","as_of_explicit":true,"as_of_raw":"April 10","source_type":"company_disclosure","comparison":null,"type":"fact","figures":null,"expiry_hint":null,"insight":null},{"id":"c5","statement":"On April 16, added system prompt brevity instruction limiting responses between tool calls to 25 words","as_of":"2026-04-16","as_of_explicit":true,"as_of_raw":"April 16","source_type":"company_disclosure","comparison":null,"type":"fact","figures":null,"expiry_hint":null,"insight":null},{"id":"c6","statement":"Limited final responses to within 100 words","as_of":"2026-04-16","as_of_explicit":false,"as_of_raw":"April 16","source_type":"company_disclosure","comparison":null,"type":"fact","figures":null,"expiry_hint":null,"insight":null},{"id":"c7","statement":"A 3% decline occurred in coding quality evaluation","as_of":"2026-04-16","as_of_explicit":false,"as_of_raw":"April 16","source_type":"company_disclosure","comparison":"baseline","type":"fact","figures":null,"expiry_hint":null,"insight":null},{"id":"c8","statement":"On April 20, reverted the system prompt brevity instruction","as_of":"2026-04-20","as_of_explicit":true,"as_of_raw":"April 20","source_type":"company_disclosure","comparison":null,"type":"fact","figures":null,"expiry_hint":null,"insight":null},{"id":"c9","statement":"Analyzed 6,852 session files and over 234,000 tool calls","as_of":"2026-04","as_of_explicit":false,"as_of_raw":"analyzed","source_type":"research_paper","comparison":null,"type":"fact","figures":null,"expiry_hint":null,"insight":null},{"id":"c10","statement":"As of April 23, reset usage limits for all subscribers","as_of":"2026-04-23","as_of_explicit":true,"as_of_raw":"as of April 23","source_type":"company_disclosure","comparison":null,"type":"fact","figures":null,"expiry_hint":null,"insight":null}],"ai_emotional_context":{"valence":0,"arousal":0,"primary_emotions":[],"secondary_emotions":[],"emotional_triggers":[]}},"provenance":{"source_chain":["primary_reporting"],"original_source_url":null,"related_articles":[]},"temporal":{"freshness":"recent","next_update_expected":null},"access":{"license":"neupai_standard","attribution_required":true,"structured_data":"free","full_text_available":false,"full_text_access":null}}