Venture firm Accel has stepped up its investment in conversational artificial-intelligence software, backing two funding rounds for companies building automated customer-service agents within two days. Decagon said it raised a $131 million Series C round co-led by Accel and Andreessen Horowitz, giving the U.S.-based company a valuation of about $1.5 billion. The startup’s AI agents handle customer inquiries for large enterprises and have already served tens of millions of end users, according to the company. In Berlin, Synthflow AI secured a $20 million Series A round led by Accel. Founded in 2023, Synthflow offers a no-code platform that lets corporations deploy white-label voice agents. The service has amassed more than 1,000 customers, processed roughly 45 million calls and plans to open its first U.S. office with the new capital. The back-to-back deals underscore intensifying investor competition for startups automating customer support, a segment analysts at MarketsandMarkets expect to grow into a nearly $50 billion global industry by 2031. Accel partner Luca Bocchio said the firm sees an inflection point for voice and text agents as enterprises seek to cut costs while meeting stricter compliance demands.