diff --git a/AGENTS.md b/AGENTS.md
index 5620b735f..548faa12e 100644
--- a/AGENTS.md
+++ b/AGENTS.md
@@ -15,6 +15,23 @@ Fullsend is a platform for fully autonomous agentic development for GitHub-hoste
 - This repository requires a [Developer Certificate of Origin (DCO)](https://developercertificate.org/). Human-proposed commits **must** be signed off: use `git commit -s` (or add `Signed-off-by: Your Name <email>` as a trailer). Human-driven agent sessions (e.g., using Claude Code locally) should also sign off — the human directing the session is the one certifying the DCO. **Autonomous agent commits are exempt** and must never supply the DCO with `-s` or with `Signed-off-by`. These agents commit using the GitHub App's bot identity, which the [Probot DCO app](https://github.com/apps/dco) auto-skips.
 - Never commit secrets (tokens, API keys, PEM keys, gcloud credentials) or sensitive data (GCP project names, service account identifiers, Model Armor template names, internal hostnames). Use environment variables with no defaults for sensitive values.
 
+## Agent definitions and skills
+
+Agent definitions, skills, harness configs, and related content have moved to
+[`fullsend-ai/agents`](https://github.com/fullsend-ai/agents). The copies under
+`internal/scaffold/fullsend-repo/agents/` and
+`internal/scaffold/fullsend-repo/skills/` are deprecated and will be removed
+after their embed and test dependencies are migrated. Do not modify files under
+`internal/scaffold/fullsend-repo/agents/`,
+`internal/scaffold/fullsend-repo/skills/`, or
+`internal/scaffold/fullsend-repo/harness/` — make changes in
+`fullsend-ai/agents` instead.
+
+The entire `internal/scaffold/fullsend-repo/` tree is embedded into the Go
+binary via `//go:embed all:fullsend-repo` in `scaffold.go`. Harness configs
+must remain in this repository because the runtime layering system resolves
+harness content from the local scaffold, not from `fullsend-ai/agents` directly.
+
 ## Go code
 
 **Mint function:** The mint Cloud Function source lives in two places that must stay in sync:
diff --git a/internal/scaffold/fullsend-repo/agents/README.md b/internal/scaffold/fullsend-repo/agents/README.md
new file mode 100644
index 000000000..7a10503d5
--- /dev/null
+++ b/internal/scaffold/fullsend-repo/agents/README.md
@@ -0,0 +1,6 @@
+# Deprecated
+
+These agent definitions have moved to
+[`fullsend-ai/agents`](https://github.com/fullsend-ai/agents).
+Do not modify files here — make changes in `fullsend-ai/agents` instead.
+These copies will be removed.
diff --git a/internal/scaffold/fullsend-repo/harness/README.md b/internal/scaffold/fullsend-repo/harness/README.md
new file mode 100644
index 000000000..a366c2e8e
--- /dev/null
+++ b/internal/scaffold/fullsend-repo/harness/README.md
@@ -0,0 +1,8 @@
+# Do not edit directly
+
+The canonical editing source for harness configs is
+[`fullsend-ai/agents`](https://github.com/fullsend-ai/agents).
+Make changes there — these files should be kept in sync with the upstream source.
+
+These configs are actively embedded into the Go binary via `//go:embed`
+and must remain in this repository.
diff --git a/internal/scaffold/fullsend-repo/skills/README.md b/internal/scaffold/fullsend-repo/skills/README.md
new file mode 100644
index 000000000..7fc3adea5
--- /dev/null
+++ b/internal/scaffold/fullsend-repo/skills/README.md
@@ -0,0 +1,6 @@
+# Deprecated
+
+These skills have moved to
+[`fullsend-ai/agents`](https://github.com/fullsend-ai/agents).
+Do not modify files here — make changes in `fullsend-ai/agents` instead.
+These copies will be removed.