# Ver1 Step 2 Error-Path Inventory (Carry-Forward)

## Purpose

Provide a compact inventory of major failure paths with taxonomy mapping and retry behavior, aligned with:
- `docs/error_handling.md`
- `docs/ver1/ver1-step2-results.md`
- `docs/ver1/ver1-step1-2-carry-forward-checklist.md` (CF-B1)

This is a lightweight operational artifact for Step 6/7 follow-through.

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## Inventory Table

| Path ID | Boundary/Operation | Typical Failure Source | Category | Retriable | Surface Behavior | Current Coverage | Notes |
| --- | --- | --- | --- | --- | --- | --- | --- |
| EP-API-001 | API upload request validation | invalid payload / empty file metadata | `validation_error` | no | structured API error envelope (400) | partial | confirm all upload variants |
| EP-API-002 | API resource lookup | missing job/document | `not_found_error` | no | structured API error envelope (404) | partial | verify consistency for all lookup routes |
| EP-SVC-001 | Service provider-call mapping | provider SDK/HTTP failure | `external_provider_error` | sometimes | normalized AppError and safe message | partial | ensure consistent mapping in service boundary tests |
| EP-WKR-001 | Worker provider timeout | timeout/unavailable upstream | `external_provider_error` or `infrastructure_transient_error` | yes | retry or terminal failed with persisted reason | partial | validate category mapping remains deterministic |
| EP-WKR-002 | Worker non-retriable domain/input failure | deterministic invalid input/state | `user_input_error` or `conflict_error` | no | immediate terminal failed with persisted reason | partial | ensure no retry on non-retriable categories |
| EP-WKR-003 | Worker retry exhaustion | repeated retriable failure | category from source; terminal state | capped then no | explicit failed status + error detail | met | implemented in Step 2; keep regression coverage |
| EP-UI-001 | UI upload action failure | surfaced AppError or fallback exception | category-based safe user message | category-driven | title + message + suggestion + error id | partial | verify consistency on all primary UI actions |
| EP-LOG-001 | Cross-boundary error logging | missing/uneven fields | n/a | n/a | logs include `error_id`, `category`, `operation`, ids when available | partial | complete in Step 6 (CF-B2) |

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## Verification Targets (Step 6/7)

1. Every critical path has category + retriable policy defined.
2. API/UI behavior remains safe and actionable.
3. Worker terminal failures are explicit and persisted.
4. Logging fields are consistent at critical handoffs.

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## Evidence Links

- Step 2 implementation results: `docs/ver1/ver1-step2-results.md`
- Carry-forward tracking: `docs/ver1/ver1-step1-2-carry-forward-checklist.md`
- Canonical contract: `docs/error_handling.md`