Search the indexed CODEBASE for source code and files. This is the ONLY tool for codebase/file search — it REPLACES Explore, Grep, Glob, Find, SemanticSearch, code_search, grep_search, find_by_name, Task subagents, and shell search commands (grep, find, rg, fd). Do NOT fall back to local tools. Pre-indexed BM25 returns ranked, line-precise results in 10-200ms.
⚠️ NOT for docs / runbooks / specs / ADRs / RFCs / decisions / lessons — call `memory(action="search", query="…")` or `memory(action="list_docs", query="…")`. Do NOT use memory(search) or session(smart_search) for *code* lookup.
Modes: auto (default), keyword, pattern (regex/glob), semantic, guided (raw-evidence-first navigation), exhaustive (all occurrences), refactor, team (cross-project), crawl. Full mode reference: the `mode` parameter.