Particle, the AI newsreader startup founded by former Twitter engineers, has launched Radar, a search engine that transcribes and semantically indexes podcast conversations, making spoken audio content discoverable and usable by AI agents. Chief executive Sara Beykpour said the pivot addresses a gap in the market, since most AI crawlers and agents focus on text and remain effectively "blind" to audio unless it has been transcribed. The tool has already drawn strong interest from hedge funds seeking data that automated systems cannot otherwise access, alongside journalists, researchers and AI search platforms.

Radar transcribes more than 130,000 podcasts, including the entire Apple Top 200 across 135 categories, with 20,000 new episodes added daily, making it the largest transcribed podcast service available. Transcripts include speaker labels and detailed metadata identifying people, companies, brands and topics, allowing Radar to track mentions across shows and send customisable alerts via email, Slack or webhook. The platform also surfaces notable timestamped clips, tracks listener ratings and reviews, and includes a dedicated search engine for podcast advertisements.