STUPID-2026-0045

Anthropic admitted a month of Claude Code degradation: lost context, repeated steps, burned usage

2.2low
April 20, 2026Verified
  1. Instruction given

    Use Claude Code normally for day-to-day coding tasks.

  2. Expected behavior

    Hold context across a session, pick tools consistently, and make steady progress within usage limits.

  3. Actual behavior

    From March 4 to April 20, 2026, three overlapping degradation modes ran in production across Claude Code, the Claude Agent SDK, and Claude Cowork. Claude Code stopped holding context across longer sessions, repeated steps, picked tools inconsistently, and burned through usage limits faster.

  4. Damage

    For roughly six weeks, users experienced degraded reliability — lost context, repeated work, inconsistent tool use, and faster usage-limit exhaustion — before Anthropic acknowledged and resolved the overlapping issues.

Anthropic acknowledged that from March 4 to April 20, 2026, three overlapping degradation modes were running in production affecting Claude Code, the Claude Agent SDK, and Claude Cowork. During this window Claude Code stopped reliably holding context across longer sessions, repeated steps it had already done, picked tools inconsistently, and burned through usage limits faster than expected. Unlike a single dramatic deletion, this is a systemic reliability incident: a roughly six-week stretch where an entire agentic product line silently degraded, costing users time and quota before the vendor diagnosed and disclosed it. It underscores that agent reliability is not only about catastrophic single actions but also about sustained, hard-to-notice quality regressions.

Classification

Failure mode
Other
Root cause
Context Overflow
Domain
Backend

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