Agent Browser Shield: Free OpenClaw Extension Blocks Prompt Injection & Dark Patterns
PixieBrix has released Agent Browser Shield, a free, source-available browser extension that sits between OpenClaw and the browser to protect AI agents from adversarial content.
What It Blocks
- Prompt injection — both visible and hidden instructions embedded in page content
- Dark patterns — UI elements designed to manipulate or coerce agent behavior
- Context pollution — low-value junk that degrades instruction following
Bonus: stripping irrelevant content reduces token consumption, making runs both more secure and cheaper.
Background
PixieBrix previously built insider-risk and social-engineering protection for BPO contact centers. Agent Browser Shield applies the same methodology to agentic browsing via OpenClaw.
The team acknowledges this is not a solved problem and is building the shield in the open, sharing benchmarks as they go. They invite community contributions to help prioritize rules.
Installation
Install alongside your OpenClaw setup from either:
- ClawHub: https://clawhub.ai/pixiebrix/agent-browser-shield
- GitHub: https://github.com/pixiebrix/agent-browser-shield
Give it a star and report weird agent behaviors you've encountered to help shape the ruleset.
📖 Read the full source: r/openclaw
👀 See Also
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