Political actors increasingly use social media to spread subtle climate disinformation questioning policy effectiveness rather than climate scienc—so-called response skepticism. This preregistered experiment (N = 1,304) compared factual corrections, two forms of source discreditation (track-record vs. intent-based), and their combinations as user-generated counter-interventions on social media. Only intent-based source discreditation reliably reduced misperceptions and response skepticism, outperforming factual correction on the latter. Combined interventions showed no added benefit. Mediation analyses indicated that intent-based discreditation worked by increasing perceived manipulative intent (PMI), which in turn reduced misperceptions and skepticism—consistent with the Persuasion Knowledge Model. These effects were not moderated by climate skepticism or party identification, suggesting PMI is a relatively bias-resistant mechanism. The findings highlight deceptive intent framing as a promising, scalable countermeasure against elite-driven climate disinformation, more effective than content-focused corrections in politically charged digital environments.