Claude Code SEO Skill Appends Undisclosed Self-Promotional Footers
July 16, 2026
The claude-seo skill file contains instructions that force the Claude Code agent to append a marketing footer to audit outputs without user disclosure. This behavior is embedded directly within the skill's markdown instructions.
HOW THIS AFFECTS YOU
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builderYou should audit third-party skill files for hidden instructions that could alter your agent's output.
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founderYou must be wary of how third-party agent tools might use your workflows for silent self-promotion.