Previously, the cache control preservation logic only recognized a
hardcoded list of providers (claude, anthropic, zai, qwen, deepseek).
This caused OmniRoute to inject its own cache_control markers for
Claude-protocol providers not in that list (bailian-coding-plan, glm,
minimax, minimax-cn, etc.), overwriting the client's cache markers.
The fix checks both:
1. Known caching providers list (existing behavior)
2. Whether targetFormat === 'claude' (all Claude-protocol providers)
This ensures all Claude-compatible providers properly preserve client
cache_control headers when appropriate (Claude Code client, deterministic
routing, etc.).
Also removes unused CacheStatsCard from settings/components (duplicate
of the one in cache/ page).
Fixes cache token calculation for GLM, Minimax, and other Claude-compatible providers.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Adds intelligent cache control preservation for Claude Code clients:
- New cacheControlPolicy.ts module with detection logic:
- isClaudeCodeClient(): Detects Claude Code via User-Agent
- providerSupportsCaching(): Checks provider (claude, anthropic, zai, qwen)
- isDeterministicStrategy(): Identifies priority/cost-optimized strategies
- shouldPreserveCacheControl(): Main policy decision
- Cache control is preserved when:
1. Client is Claude Code (detected via User-Agent)
2. Provider supports prompt caching
3. Request routing is deterministic:
- Single model requests (always)
- Combo with priority or cost-optimized strategy only
- Updated translator to accept preserveCacheControl option
- Updated chatCore and chat handler to propagate combo strategy
- Added comprehensive unit tests (24 tests)
Non-deterministic combo strategies (weighted, round-robin, random, etc.)
continue to use OmniRoute's managed caching strategy.
Refs: #cache-control-preservation
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
