So Claude Code, Codex, OpenCode, etc keep their normal tools/capabilities rather than being reimplemented inside a new proprietary agent. If a harness has its own indexing/code-search story, you still get that; if it doesn’t, ctx doesn’t provide additional tools like codebase indexing.
The only additional tools we do provide are orchestration-related: - local merge queue for agents (submit your diff and make sure it lands cleanly on others) - agnostic subagents (for example, a Claude Code primary agent can invoke a Codex subagent)
This reduces tool calls (and thus saves times and tokens) because instead of „trying“ / „guessing“ names repeatedly, tools like claude code typically get useful search results on the first try.
Claude for example may search for „dbal“ via regex, but the function name is „sql“ - semantic search will find that while for regex, claude would try 3 additional guesses before it actually finds what its looking for. Hope this helps!