diff --git a/harnesses/composites/customer-script/v1/harness.yaml b/harnesses/composites/customer-script/v1/harness.yaml
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+kind: composite
+name: customer-script
+version: 1
+description: >-
+  Minimal harness for customer-authored `kind: customer_script` nodes
+  (spec/tenant-namespaces.md SCR-1..SCR-6 in agent-runtimes). No LLM turn —
+  runs via the "shell" runner, agent-repo/v1 clone access only. Per-script
+  credential/secret needs are deliberately NOT baked into this base (SCR-6:
+  "an explicit, narrow allowlist... reviewed per script, not inherited
+  wholesale") — compose a `customer-script-<need>/v1` variant layering
+  whichever specific git-credential context (e.g. gitea-ssh/v1, or a
+  read-only variant) and/or `secrets_required` account_ref entries a given
+  script actually needs, rather than widening this shared base.
+
+layers:
+  - context: agent-repo/v1