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  "title": "OpenAPPA",
  "description": "OpenAPPA is a deterministic guardrail layer that intercepts agent tool calls and verifies data flows against declarative policies, blocking data exfiltration from prompt injection or hallucination without breaking agent function. Open source: yes (MIT); self-hostable; pricing free. Runs in-process; 26 stars; active.",
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  "one_liner": "OpenAPPA intercepts agent tool calls and checks their data flows against declarative policies, blocking exfiltration from prompt injection or hallucination.",
  "open_source": "yes",
  "self_hostable": "yes",
  "pricing_model": "free",
  "who_its_for": "An engineer giving an agent tools that touch sensitive data who wants a deterministic, policy-driven check on the data FLOW — what leaves and where it goes — rather than a probabilistic injection classifier, and who can run the guard in-process alongside the agent.",
  "who_its_not_for": "Teams wanting a hosted, managed security service, or those unwilling to author declarative data-flow policies up front.",
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    "note": "MIT per repo; 26 stars; 668 commits; runs in-process; intercepts tool calls and verifies data flows against declarative policies. Vendor (Archestra AI) reported: successful attacks 0% (OpenAPPA) vs 10% (Claude auto-mode) and 31% (FIDES); task completion 89% vs 90% and 41% respectively (github.com/archestra-ai/openappa + openappa.com, verified 2026-09-28)."
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  "caveats": "Verified from the primary repo and openappa.com (2026-09-28); no independent testing here. The 0%-attack / 89%-completion figures against Claude auto-mode (10% / 90%) and FIDES (31% / 41%) are the vendor's own benchmark (vendor-claim), not independently reproduced — reproduce on your own tools and data before trusting the numbers. At 26 stars this is young; the policy layer is only as good as the policies you write.",
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      "text": "OpenAPPA is a deterministic guardrail layer that intercepts agent tool calls and verifies data flows against declarative policies, blocking data exfiltration from prompt injection or hallucination without breaking agent function. Open source: yes (MIT); self-hostable; pricing free. It runs in-process, has 26 stars, and is active (668 commits)."
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      "text": "OpenAPPA is a deterministic guardrail layer that intercepts agent tool calls and verifies data flows against declarative policies, blocking data exfiltration from prompt injection or hallucination without breaking agent function. Open source: yes (MIT); self-hostable; pricing free. It runs in-process, has 26 stars, and is active (668 commits).\n\nOpenAPPA sits between an agent and its tools and reasons about data movement rather than message text. When the agent tries to call a tool, OpenAPPA checks the data flow that call would create against declarative policies — what data is leaving, and to where — and deterministically blocks flows that would exfiltrate sensitive data, whether the trigger was a prompt injection or a plain hallucination. The stated design goal is to do this without breaking the agent's legitimate function: block the leak, keep the task working. It runs in-process alongside the agent (no separate service). Open source: yes (MIT); self-hostable; pricing free."
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      "text": "sensitive data, whether the trigger was a prompt injection or a plain hallucination. The stated design goal is to do this without breaking the agent's legitimate function: block the leak, keep the task working. It runs in-process alongside the agent (no separate service). Open source: yes (MIT); self-hostable; pricing free.\n\n- MIT per repo; 26 stars; 668 commits; in-process; intercepts tool calls and verifies data flows against declarative policies (github.com/archestra-ai/openappa + openappa.com, verified 2026-09-28).\n- Vendor (Archestra AI) benchmark: successful attacks 0% vs 10% for Claude auto-mode and 31% for FIDES; task completion 89% vs 90% and 41%. Stated here as the vendor's own numbers (vendor-claim), not independently reproduced.\n- Curated from the GTM Stacker signal registry (2026-09-28 pass); license/facts independently verified 2026-09-28."
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      "text": "2026-09-28). - Vendor (Archestra AI) benchmark: successful attacks 0% vs 10% for Claude auto-mode and 31% for FIDES; task completion 89% vs 90% and 41%. Stated here as the vendor's own numbers (vendor-claim), not independently reproduced. - Curated from the GTM Stacker signal registry (2026-09-28 pass); license/facts independently verified 2026-09-28.\n\nA GTM agent with CRM, inbox, and enrichment access holds exactly the data an exfiltration attack wants — and the dangerous failure is not a wrong answer but a correct-looking tool call that ships that data somewhere it should not go. OpenAPPA targets that class deterministically: it gates on the data flow the call produces, not on spotting the injecting text, and aims to keep legitimate work flowing. Open source: yes (MIT); self-hostable; pricing free. The honest read: the vendor's headline (0% attacks, 89% task completion, beating Claude auto-mode and FIDES) is its own benchmark and the project is young at 26 stars — the mechanism is well-aimed, but pilot it on your own sensitive tools and write real policies before trusting it in front of live data."
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