Which harnesses can search the web without an add-on?

Not surveyed yet. No implementation of this capability has been read from source, so there is no comparison to show — only the list of what is on file, below. The dimensions worth comparing are decided by reading the implementations, not before.

Present but not verified. 10 tools, registered by 9 harnesses, have not been read from source: Claude Code WebSearch, dsh web_search, Grok Build web_search, Hermes web_search, Kimi Code web-search, MiMo Code codesearch, MiMo Code websearch, OpenClaw web_search, opencode websearch, Qwen Code web_search.