diff --git a/checkpoint.json b/checkpoint.json
new file mode 100644
index 000000000..3bafaa8aa
--- /dev/null
+++ b/checkpoint.json
@@ -0,0 +1,62 @@
+{
+  "timestamp": "2026-03-25T19:56:04.263338Z",
+  "current_node": "main",
+  "completed_nodes": [
+    "start",
+    "main"
+  ],
+  "node_retries": {
+    "main": 1,
+    "start": 1
+  },
+  "context_values": {
+    "response.main": "Here's a summary of all results:\n\n| # | Command | Result |\n|---|---------|--------|\n| 1 | `rustc --version && cargo --version` | ✅ **PASS** — rustc 1.94.0, cargo 1.94.0 |\n| 2 | `bun --version` | ✅ **PASS** — bun 1.3.10 |\n| 3 | `cargo fmt --check --all` | ✅ **PASS** — no formatting issues |\n| 4 | `cargo clippy -q --workspace -- -D warnings` | ✅ **PASS** — no lint warnings |\n| 5 | `cargo nextest run --cargo-quiet --workspace --status-level fail` | ✅ **PASS** — 3,475 tests passed, 178 skipped (1 slow), 0 failed |\n| 6 | `cd apps/fabro-web && bun install && bun run typecheck` | ✅ **PASS** — 1,400 packages installed, no type errors |\n| 7 | `cd apps/fabro-web && bun test` | ✅ **PASS** — 15 tests passed across 3 files, 0 failed |\n\n**All 7 steps passed.** The sandbox is fully functional for linting and testing the project.",
+    "internal.node_visit_count": 1,
+    "internal.retry_count.main": 1,
+    "internal.fidelity": "compact",
+    "internal.thread_id": "start",
+    "internal.run_id": "01KMK8583D646EVN7B6TEWBY2R",
+    "failure_class": "",
+    "internal.retry_count.start": 1,
+    "current.preamble": "Goal: Verify the sandbox can lint and test the project\n",
+    "current_node": "main",
+    "outcome": "success",
+    "failure_signature": "",
+    "graph.goal": "Verify the sandbox can lint and test the project",
+    "thread.start.current_node": "main",
+    "last_response": "Here's a summary of all results:\n\n| # | Command | Result |\n|---|---------|--------|\n| 1 | `rustc --version && cargo --version` | ✅ **PASS** — rustc 1.94.0, cargo 1.94.0 |\n| 2 | `bun --version` | ",
+    "graph.rankdir": "LR",
+    "last_stage": "main"
+  },
+  "logs": [],
+  "node_outcomes": {
+    "start": {
+      "status": "success",
+      "duration_ms": 0
+    },
+    "main": {
+      "status": "success",
+      "context_updates": {
+        "response.main": "Here's a summary of all results:\n\n| # | Command | Result |\n|---|---------|--------|\n| 1 | `rustc --version && cargo --version` | ✅ **PASS** — rustc 1.94.0, cargo 1.94.0 |\n| 2 | `bun --version` | ✅ **PASS** — bun 1.3.10 |\n| 3 | `cargo fmt --check --all` | ✅ **PASS** — no formatting issues |\n| 4 | `cargo clippy -q --workspace -- -D warnings` | ✅ **PASS** — no lint warnings |\n| 5 | `cargo nextest run --cargo-quiet --workspace --status-level fail` | ✅ **PASS** — 3,475 tests passed, 178 skipped (1 slow), 0 failed |\n| 6 | `cd apps/fabro-web && bun install && bun run typecheck` | ✅ **PASS** — 1,400 packages installed, no type errors |\n| 7 | `cd apps/fabro-web && bun test` | ✅ **PASS** — 15 tests passed across 3 files, 0 failed |\n\n**All 7 steps passed.** The sandbox is fully functional for linting and testing the project.",
+        "last_response": "Here's a summary of all results:\n\n| # | Command | Result |\n|---|---------|--------|\n| 1 | `rustc --version && cargo --version` | ✅ **PASS** — rustc 1.94.0, cargo 1.94.0 |\n| 2 | `bun --version` | ",
+        "last_stage": "main"
+      },
+      "notes": "Stage completed: main",
+      "usage": {
+        "model": "claude-sonnet-4-6",
+        "input_tokens": 2324,
+        "output_tokens": 1078,
+        "cache_read_tokens": 32873,
+        "cache_write_tokens": 12712,
+        "reasoning_tokens": 16,
+        "cost": 0.023142
+      },
+      "duration_ms": 330982
+    }
+  },
+  "next_node_id": "exit",
+  "node_visits": {
+    "start": 1,
+    "main": 1
+  }
+}
\ No newline at end of file
diff --git a/nodes/main/prompt.md b/nodes/main/prompt.md
new file mode 100644
index 000000000..c2f632b7f
--- /dev/null
+++ b/nodes/main/prompt.md
@@ -0,0 +1,14 @@
+Goal: Verify the sandbox can lint and test the project
+
+
+Run each of these commands in order and report the results. If any command fails, continue running the rest and report all results at the end.
+
+1. rustc --version && cargo --version
+2. bun --version
+3. cargo fmt --check --all
+4. cargo clippy -q --workspace -- -D warnings
+5. cargo nextest run --cargo-quiet --workspace --status-level fail
+6. cd apps/fabro-web && bun install && bun run typecheck
+7. cd apps/fabro-web && bun test
+
+Report a summary table of pass/fail for each step.
\ No newline at end of file
diff --git a/nodes/main/provider_used.json b/nodes/main/provider_used.json
new file mode 100644
index 000000000..d0418b4c6
--- /dev/null
+++ b/nodes/main/provider_used.json
@@ -0,0 +1,5 @@
+{
+  "mode": "agent",
+  "provider": "anthropic",
+  "model": "claude-sonnet-4-6"
+}
\ No newline at end of file
diff --git a/nodes/main/response.md b/nodes/main/response.md
new file mode 100644
index 000000000..2f4c4740f
--- /dev/null
+++ b/nodes/main/response.md
@@ -0,0 +1,13 @@
+Here's a summary of all results:
+
+| # | Command | Result |
+|---|---------|--------|
+| 1 | `rustc --version && cargo --version` | ✅ **PASS** — rustc 1.94.0, cargo 1.94.0 |
+| 2 | `bun --version` | ✅ **PASS** — bun 1.3.10 |
+| 3 | `cargo fmt --check --all` | ✅ **PASS** — no formatting issues |
+| 4 | `cargo clippy -q --workspace -- -D warnings` | ✅ **PASS** — no lint warnings |
+| 5 | `cargo nextest run --cargo-quiet --workspace --status-level fail` | ✅ **PASS** — 3,475 tests passed, 178 skipped (1 slow), 0 failed |
+| 6 | `cd apps/fabro-web && bun install && bun run typecheck` | ✅ **PASS** — 1,400 packages installed, no type errors |
+| 7 | `cd apps/fabro-web && bun test` | ✅ **PASS** — 15 tests passed across 3 files, 0 failed |
+
+**All 7 steps passed.** The sandbox is fully functional for linting and testing the project.
\ No newline at end of file
diff --git a/nodes/main/status.json b/nodes/main/status.json
new file mode 100644
index 000000000..7a9570e68
--- /dev/null
+++ b/nodes/main/status.json
@@ -0,0 +1,6 @@
+{
+  "status": "success",
+  "notes": "Stage completed: main",
+  "failure_reason": null,
+  "timestamp": "2026-03-25T19:56:04.261101+00:00"
+}
\ No newline at end of file
diff --git a/nodes/start/status.json b/nodes/start/status.json
new file mode 100644
index 000000000..a4928681a
--- /dev/null
+++ b/nodes/start/status.json
@@ -0,0 +1,6 @@
+{
+  "status": "success",
+  "notes": null,
+  "failure_reason": null,
+  "timestamp": "2026-03-25T19:39:54.097687+00:00"
+}
\ No newline at end of file