**The `auto` and `parallel` meta search engines have been removed** (including the `meta` and `parallel_scientific` aliases). The default langgraph-agent strategy replaces them — it selects search engines dynamically per query, so a separate LLM-based engine picker is redundant. Stored values (`search.tool` setting, news subscriptions, queued researches, saved benchmark configs) are migrated automatically on upgrade (migration 0013; `search.tool` values pointing at a removed engine become `searxng`). **What to do:** API callers passing `search_tool="auto"` or `"parallel"` must pick a concrete engine (e.g. `searxng`), and `LDR_SEARCH_TOOL=auto` environment overrides must be updated likewise.
