id: CORE-001D2B
title: Options Chain and Expiration Boundary Normalization
status: done
priority: P1
effort: S
depends_on:
  - CORE-001D2A
tags:
  - core
  - decimal
  - options
  - cache
  - provider
summary: Option expirations and options-chain payloads now use explicit cache/provider normalization boundaries with malformed cached payload discard rules.
completed_notes:
  - Added named normalization adapters for option expirations and options-chain payloads in `app/services/data_service.py`.
  - Cached payload symbol mismatches are discarded instead of being silently reused.
  - Malformed cached list-shape payloads are discarded and refreshed rather than being treated as valid empty results.
  - Fresh provider payloads are normalized before caching.
  - Added focused coverage in `tests/test_options_normalization.py`.
  - Validated with focused pytest coverage, `make build`, and a targeted browser-visible `/options` check on `main`.