composite

• FD-2026-002 CDN edge degradation (Fastly, June 2021) real-world severe ↯
• FD-2026-003 Elevated latency + partial 5xx (AWS us-east-1, Nov 2020) real-world severe ↯

corruption

• FD-2026-011 Truncated JSON body moderate ↯
• FD-2026-012 Malformed JSON (trailing comma) trivial ↯
• FD-2026-013 Wrong types in a valid envelope moderate ↯
• FD-2026-014 Encoding mismatch (claims UTF-8, sends Latin-1) moderate ↯
• FD-2026-015 UTF-8 BOM prefix trivial ↯

headers

• FD-2026-008 WAF challenge page instead of JSON (Cloudflare pattern) real-world moderate ↯
• FD-2026-019 JSON body, text/plain label moderate ↯

latency

• FD-2026-006 Total reachability loss (Meta BGP withdrawal, Oct 2021) real-world fatal ↯
• FD-2026-016 Slow but correct response moderate ↯
• FD-2026-017 Connection accepted, never replies severe ↯
• FD-2026-018 Partial body then stall severe ↯

redirect

• FD-2026-020 Infinite redirect loop moderate ↯

sequence

• FD-2026-007 Recovering outage (Slack, Jan 2021) real-world severe ↯

status

• FD-2026-001 Stripe-style rate limit real-world moderate ↯
• FD-2026-004 GitHub secondary rate limit real-world moderate ↯
• FD-2026-005 Token expires mid-session (Entra ID pattern) real-world moderate ↯
• FD-2026-009 Provider overloaded (OpenAI-style 529) real-world moderate ↯
• FD-2026-010 Gateway timeout from the edge (Cloudflare 522 pattern) real-world severe ↯