The core claim is strongly supported by Reuters, which reported on April 21, 2026 that Meta was installing tracking software on U.S.-based employees' computers to capture mouse movements and keystrokes for AI training data. The originating X post echoes that Reuters report. Secondary corroboration from Computerworld and Ars Technica is consistent with Reuters' description that the monitoring was tied to training AI agents. Confidence is medium rather than high because the best evidence available here is a Reuters report based on internal memos rather than a directly fetched Meta official statement or memo.