Phase 12: ai_client rethrow classification (6 sites).
Site 1 (L276 _load_credentials): added 'from e' (Pattern 1)
Sites 2+3 (L878+L879 _default_send nested): added 'from None' (Pattern 1)
Site 4 (L1336 _list_anthropic_models): migrated to Result (the broken
'raise ErrorInfo from exc' runtime bug — same pattern as Phase 10 site 1)
Site 5 (L2078 _send inside _send_gemini_cli): added 'from None' (Pattern 1)
Site 6 (L2759 _dashscope_call): added 'from None' (Pattern 1)
KNOWN LIMITATION: the audit script does not have a heuristic for
'raise X from e' or 'from None' (Pattern 1 compliant). The 5 Pattern 1
sites remain classified as INTERNAL_RETHROW ('suspicious but not
violation') in the audit. Strict mode (Phase 14 gate) accepts this.
Adding a Pattern 1 heuristic requires Tier 1 approval per the
conventions ('Never modify audit heuristics without explicit Tier 1
approval'). Documented in the end-of-track report.
Audit state (after Phase 12):
mcp_client: 0 migration-target (Phase 3-8 complete)
ai_client: 7 -> 6 migration-target (5 RETHROW + 0 SS + 0 BC + 0 UNCLEAR)
BC: 0 (Phase 10)
SS: 0 (Phase 11)
RETHROW: 7 -> 6 (one site migrated to Result in Phase 12)
UNCLEAR: 0
COMPLIANT: 33 -> 34 (+1)
rag_engine: 9 migration-target (Phase 13)
Tests: 109 pass (was 97; +12 Phase 12 site/invariant tests).
ed
a9969563dc