Degraded performance for multiple models

What to do

• Check whether you use Anthropic claude.ai, Claude API (api.anthropic.com), Claude Code, Claude Cowork. Check your stack

  Paste a package.json, lockfile, Terraform or a list of domains at down.guide/stack to see every provider you depend on.

• Confirm your retries, queues and scheduled jobs caught up after the 2h 41m it lasted.

  Anything that failed between 2026-08-18 16:20 UTC and 2026-08-18 19:01 UTC may need a replay.

• Subscribe to Anthropic's feed to hear about the next one first. RSS feed

  https://down.guide/feed?provider=anthropic works in Slack (/feed subscribe), Discord feed bots and any RSS reader.

Updates from Anthropic 5

1. investigatingAug 18, 2026, 4:20 PM UTC

   We are investigating reports of degraded performance affecting multiple models. We will provide an update as soon as possible.

   provider

2. investigatingAug 18, 2026, 4:20 PM UTC

   We are investigating elevated errors on requests to Claude Mythos 5, Claude Fable 5, Claude Opus 5, Claude Sonnet 5, Claude Haiku 4.5, and other Claude models. We will provide an update as soon as possible.

   provider

3. investigatingAug 18, 2026, 5:12 PM UTC

   We are investigating elevated errors on requests to Claude Opus 5. We will provide an update as soon as possible.

   provider

4. monitoringAug 18, 2026, 6:26 PM UTC

   A fix has been implemented and we are monitoring the results.

   provider

5. resolvedAug 18, 2026, 7:01 PM UTC

   The issue affecting Claude Opus 5 has been resolved. Impact occurred from 16:11 to 18:23 UTC.

   provider

Corrections

None so far.

Something wrong on this page? Report an error or send us a note. Every fix is listed here.