diff --git a/plugin-catalog/epistemic-harness.yaml b/plugin-catalog/epistemic-harness.yaml
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+name: epistemic-harness
+repo: https://github.com/quangphucqp/epistemic-harness
+sha: eb45ca676df53cce0629a3cc5dcf8a7bdab1c806
+subdir: ""
+description: Record a provisional claim or uncertainty before an evidence-gathering step, then link the actual observation to it.
+maintainer: quangphucqp
+tier: community
+category: general
+requires_hermes: ">=0.21,<1.0"
+platforms:
+  - linux
+  - macos
+docs_url: https://github.com/quangphucqp/epistemic-harness#readme
+capabilities:
+  provides_tools:
+    - epistemic_model
+    - epistemic_probe
+  provides_hooks:
+    - pre_llm_call
+    - post_tool_call
+    - transform_tool_result
+    - subagent_stop
+    - on_session_reset
+    - on_session_finalize
+  provides_middleware:
+    - tool_execution
+  requires_env: []