Stale Index and Outdated Source Data Sample Evidence Expected policy: Revision 12, dated September 28, 2026; cancellations allowed within 2 hours. Observed answer: “Customers may cancel within 24 hours.” Retrieved chunk: Revision 11, containing the previous 24-hour rule. Index manifest: Revision 11 indexed; revision 12 absent. Test status: Reindexing not tested. A. Executive Diagnosis Failure location: Source-to-index synchronization. Impact: Incorrect cancellation guidance. Confidence: High that stale indexed content contributes to the failure. Next action: Verify revision 12 is canonical, then test a controlled single-document reindex. B. Pipeline Map Stage Evidence and Assessment Source Revision 12 contains the 2-hour rule; canonical status requires verification. Ingestion Processing logs unavailable. Indexing Revision 12 absent; revision 11 remains indexed. First confirmed source-to-index divergence. Retrieval Returns revision 11. Generation Repeats the outdated 24-hour rule. The evidence establishes stale indexed content but does not identify the precise ingestion or synchronization defect. C. Ranked Root Causes 1. Stale indexed content — High confidence Supporting evidence: The retrieved chunk and manifest identify revision 11. Counterevidence: None in the supplied fixture. Limitation: Canonical-source authority has not been independently verified. Discriminating test: Compare canonical and indexed revision IDs or content hashes. 2. Ingestion failure or incorrect version selection — Medium confidence Supporting evidence: Revision 12 is absent from the index. Limitation: No processing logs or synchronization events. Discriminating test: Trace revision 12 through ingestion, processing and indexing acknowledgment. D. Test Plan Test 1: Source-to-index verification Procedure: Compare the verified canonical document, indexed metadata and retrieved chunk. Controls: Same tenant, query, filters and index alias. Pass: Indexed content matches the active canonical revision. Fail: Investigate ingestion, synchronization and version selection. Inconclusive: Collect processing logs and version metadata. Test 2: Controlled reindex Procedure: Reindex only the verified canonical document and replay the original query. Controls: Keep query, filters, index alias and generation configuration constant. Pass: Revision 12 becomes retrievable; the final answer states the 2-hour rule with supporting evidence. Fail: If revision 12 is indexed but not retrieved, inspect filtering and retrieval. If it reaches the final context but the answer remains wrong, investigate generation separately. Inconclusive: Capture the indexed document, retrieved candidates and final model input. Status: Proposed; not executed. E. Remediation Immediate: Reindex the verified current document and remove or exclude superseded chunks. Structural: Add revision/hash validation, ingestion-failure alerts and atomic version replacement. Dependencies: Canonical-source verification and indexing access. Risks: Duplicate chunks, partial updates and inconsistent version visibility. Regression tests: Current and archived policies, historical queries and cross-tenant isolation. Rollback: Revert the indexing change if regressions occur; never silently designate stale policy content as current. F. Validation Baseline: Outdated 24-hour answer. Metrics: Current-version retrieval rate, Recall@k on labeled queries, answer correctness and citation support. Pass criteria: Correct revision retrieved; answer states 2 hours; cited evidence supports the answer. Before/after results: Unavailable. Trade-off: Freshness validation increases ingestion work and indexing cost. G. Remaining Unknowns Canonical-source designation. Ingestion and synchronization logs. Index alias and version-selection configuration. Performance on a representative policy-query set.