diff --git a/checkpoint.json b/checkpoint.json
new file mode 100644
index 000000000..49482f49b
--- /dev/null
+++ b/checkpoint.json
@@ -0,0 +1,52 @@
+{
+  "timestamp": "2026-03-20T01:26:23.087522Z",
+  "current_node": "toolchain",
+  "completed_nodes": [
+    "start",
+    "toolchain"
+  ],
+  "node_retries": {
+    "start": 1,
+    "toolchain": 1
+  },
+  "context_values": {
+    "internal.node_visit_count": 1,
+    "thread.start.current_node": "toolchain",
+    "outcome": "success",
+    "current.preamble": "Goal: # Decompose `fabro run` into `create` / `start` / `attach`\n\n## Context\n\n`fabro run` currently does everything in a single process: creates the run directory, sets up the event system, builds the sandbox, runs the workflow engine, writes the conclusion, and renders live progress. The `--detach` flag is a bolt-on that spawns a child process by reconstructing CLI argv — brittle and not composable.\n\nThe goal is to decompose into three primitives (Docker-style):\n- **`fabro create`** — allocate run, persist spec, return run ID\n- **`fabro start`** — spawn a detached engine process (always a separate process)\n- **`fabro attach`** — tail progress.jsonl with live rendering + handle interviews\n\nCompositions:\n- `fabro run` = create + start + attach (attach opens the file before start, guaranteeing zero missed events)\n- `fabro run --detach` = create + start + print run ID\n- Standalone `fabro attach <id>` = reconnect to any running/finished run\n\n## Key design decisions\n\n### 1. Attach absorbs `run_progress.rs`\nThe existing `ProgressUI` (indicatif spinners, stage tracking, tool call rendering) moves into `attach`. Rather than building a new renderer, we add a `handle_json_line(&str)` method to ProgressUI that parses JSONL envelopes and dispatches to the same internal rendering methods (`on_stage_started`, `finish_stage`, `on_tool_call_started`, etc.). This preserves 100% rendering fidelity.\n\nThe dispatch pattern already exists in `format_event_pretty()` in `logs.rs` — match on the `\"event\"` string field, extract typed values from JSON. The internal ProgressUI methods already take simple types (strings, ints), not `WorkflowRunEvent`.\n\n`handle_event(&WorkflowRunEvent)` stays for any in-process callers (API server).\n\n### 2. File-based interview IPC\nThe engine process uses a new `FileInterviewer` (impl Interviewer) that:\n- Writes `interview_request.json` (serialized `Question`) to run_dir\n- Polls for `interview_response.json` in run_dir\n- Deserializes the `Answer`, cleans up both files\n\nThe attach loop watches for `interview_request.json`:\n1. Hides indicatif bars (same as `ProgressAwareInterviewer` does today)\n2. Prompts user via `ConsoleInterviewer` logic\n3. Writes `interview_response.json`\n4. Shows bars again\n\n`Question` and `Answer` already derive `Serialize`/`Deserialize`.\n\n### 3. RunSpec persistence\n`create` writes `spec.json` to run_dir — a serializable struct with all CLI args needed to run the engine. Replaces the argv-reconstruction in `detach_run()`.\n\n### 4. Engine invocation\n`start` spawns `fabro _run_engine --run-dir <dir>` — a hidden internal command that reads `spec.json` and executes the workflow. The child uses `FileInterviewer` instead of `ConsoleInterviewer`.\n\n### 5. Stdin and Ctrl+C\n- `fabro run` (foreground): Ctrl+C sends SIGTERM to child (via `run.pid`), waits for conclusion, then exits\n- `fabro attach` (standalone): Ctrl+C just detaches, run continues\n- Engine process stdin is always `/dev/null` — interviews go through file-based IPC, not stdin\n\n---\n\n## Implementation plan\n\n### Phase 1: Foundation — RunSpec + extract engine\n\n**Step 1: RunSpec struct**\n- New file: `lib/crates/fabro-workflows/src/run_spec.rs`\n- `#[derive(Serialize, Deserialize)]` struct: run_id, workflow_path (absolute), dot_source, working_directory, goal, model, provider, sandbox_provider, labels, verbose, no_retro, ssh, preserve_sandbox, dry_run, auto_approve, resume, run_branch\n- Methods: `save(run_dir)`, `load(run_dir)`\n- Register in `lib/crates/fabro-workflows/src/lib.rs`\n\n**Step 2: FileInterviewer**\n- New file: `lib/crates/fabro-interview/src/file.rs`\n- `FileInterviewer { run_dir: PathBuf }` implementing `Interviewer`\n- `ask()`: write `interview_request.json`, poll for `interview_response.json` (100ms interval, respect timeout from Question), deserialize Answer, clean up files\n- Register in `lib/crates/fabro-interview/src/lib.rs`\n\n**Step 3: Extract `run_engine()` from `run_command()`**\n- Modify: `lib/crates/fabro-cli/src/commands/run.rs`\n- New function: `run_engine(spec, run_dir, run_defaults, styles, github_app, git_author) -> Result<()>`\n- Contains lines ~629–end of current `run_command()`: EventEmitter + JSONL writer + cost accumulator + git SHA tracker, sandbox creation, engine execution, conclusion writing, retro, PR creation, cleanup\n- Does NOT register ProgressUI — only writes progress.jsonl\n- Uses `FileInterviewer` instead of `ConsoleInterviewer`/`ProgressAwareInterviewer`\n\n**Step 4: Hidden `_run_engine` command**\n- Modify: `lib/crates/fabro-cli/src/main.rs`\n- Add `_RunEngine { run_dir: PathBuf }` to `Command` enum (hidden)\n- Handler: load `spec.json`, load cli_config/github_app/git_author, call `run_engine()`\n\n### Phase 2: Attach — ProgressUI from JSONL + interview handling\n\n**Step 5: Add `handle_json_line` to ProgressUI**\n- Modify: `lib/crates/fabro-cli/src/commands/run_progress.rs`\n- New method: `handle_json_line(&mut self, line: &str)` that parses envelope JSON and dispatches to existing internal methods:\n  - `\"Sandbox.Initializing\"` / `\"Sandbox.Ready\"` → `on_sandbox_event()`\n  - `\"SetupStarted\"` / `\"SetupCompleted\"` → `on_setup_started/completed()`\n  - `\"StageStarted\"` → `on_stage_started(node_id, name, script)`\n  - `\"StageCompleted\"` → extract fields, call `finish_stage()`\n  - `\"StageFailed\"` → `finish_stage()` + error info\n  - `\"Agent.ToolCallStarted\"` / `\"Agent.ToolCallCompleted\"` → `on_tool_call_started/completed()`\n  - `\"Agent.AssistantMessage\"` → update stage model display\n  - `\"Agent.CompactionCompleted\"` → compaction bar\n  - `\"ParallelBranchStarted\"` / `\"ParallelBranchCompleted\"` → branch tracking\n  - `\"RetroStarted\"` / `\"RetroCompleted\"` / `\"RetroFailed\"` → retro spinner\n  - `\"SshAccessReady\"` → SSH command display\n  - etc.\n- Follows the same pattern as `format_event_pretty()` in `logs.rs` but calls internal rendering methods instead of formatting strings\n\n**Step 6: Attach command**\n- New file: `lib/crates/fabro-cli/src/commands/attach.rs`\n- `attach_run(run_dir, kill_on_detach: bool) -> Result<ExitCode>`:\n  1. Read `spec.json` for header info (run_id, workflow name)\n  2. Create ProgressUI, show header (version, run_id, time, run_dir)\n  3. Poll loop (100ms):\n     - Read new lines from `progress.jsonl`, feed to `progress_ui.handle_json_line()`\n     - Check for `interview_request.json` → hide bars, prompt via ConsoleInterviewer, write `interview_response.json`, show bars\n     - Exit when `conclusion.json` exists and no new lines\n  4. Read `conclusion.json` for exit code: Success/PartialSuccess → 0, else → 1\n- Ctrl+C: if `kill_on_detach`, SIGTERM to child PID from `run.pid`; otherwise print \"Detached\" and exit 0\n- Add `Attach { run: String, verbose: bool }` to `Command` enum\n- Handler: `run_lookup::resolve_run()`, call `attach_run()`\n\n### Phase 3: Create + Start commands\n\n**Step 7: Create command**\n- New file: `lib/crates/fabro-cli/src/commands/create.rs`\n- `create_run(args, run_defaults, styles) -> Result<(String, PathBuf)>`:\n  - Extract lines ~440–627 from `run_command()`: resolve workflow, parse graph, validate, resolve sandbox/model/provider, create run_dir, write graph.fabro/id.txt/status.json(Submitted)/spec.json\n  - Returns (run_id, run_dir)\n- Add `Create` variant to `Command` enum (same args as RunArgs minus --detach/--run-id/--run-dir)\n\n**Step 8: Start command**\n- New file: `lib/crates/fabro-cli/src/commands/start.rs`\n- `start_run(run_dir, inherit_stdin: bool) -> Result<u32>` (returns child PID):\n  - Validate status.json is `Submitted`\n  - Spawn `fabro _run_engine --run-dir <dir>` as detached child (setsid, stdout/stderr → detach.log, stdin → /dev/null)\n  - Write child PID to `run.pid`\n  - Return PID\n- Add `Start { run: String }` to `Command` enum\n- Handler: resolve run, call `start_run()`\n\n### Phase 4: Recompose `fabro run`\n\n**Step 9: Rewrite `run_command()` as composition**\n- `fabro run` (foreground):\n  ```\n  let (run_id, run_dir) = create_run(args, ...)?;\n  let _child_pid = start_run(&run_dir)?;\n  let exit_code = attach_run(&run_dir, kill_on_detach=true)?;\n  std::process::exit(exit_code);\n  ```\n- `fabro run --detach`:\n  ```\n  let (run_id, run_dir) = create_run(args, ...)?;\n  start_run(&run_dir)?;\n  println!(\"{run_id}\");\n  ```\n- Delete `detach_run()` from main.rs\n- Deprecate `--run-id` / `--run-dir` hidden flags\n\n### Phase 5: Cleanup + testing\n\n**Step 10: Tests**\n- `run_spec.rs`: save/load roundtrip\n- `file.rs` (FileInterviewer): write request → write response → verify ask() returns correct answer\n- `run_progress.rs`: test `handle_json_line` with sample JSONL lines (stage started/completed, tool calls, etc.)\n- `attach.rs`: integration test — write JSONL lines to a temp file, verify attach loop renders and exits correctly\n- Existing tests remain unchanged\n\n**Step 11: Remove dead code**\n- Delete `detach_run()` from main.rs\n- Remove `--run-id` / `--run-dir` args from RunArgs\n- `ProgressAwareInterviewer` moves into attach.rs (or gets deleted if attach handles the coordination directly)\n\n---\n\n## Files summary\n\n| File | Action |\n|------|--------|\n| `lib/crates/fabro-workflows/src/run_spec.rs` | **New** — RunSpec struct |\n| `lib/crates/fabro-workflows/src/lib.rs` | Modify — register run_spec module |\n| `lib/crates/fabro-interview/src/file.rs` | **New** — FileInterviewer |\n| `lib/crates/fabro-interview/src/lib.rs` | Modify — register file module |\n| `lib/crates/fabro-cli/src/commands/create.rs` | **New** — create logic extracted from run.rs |\n| `lib/crates/fabro-cli/src/commands/start.rs` | **New** — spawn detached engine process |\n| `lib/crates/fabro-cli/src/commands/attach.rs` | **New** — attach loop + interview handling |\n| `lib/crates/fabro-cli/src/commands/run_progress.rs` | Modify — add `handle_json_line()` method |\n| `lib/crates/fabro-cli/src/commands/run.rs` | Modify — extract run_engine(), rewrite run_command() as composition |\n| `lib/crates/fabro-cli/src/commands/mod.rs` | Modify — register new modules |\n| `lib/crates/fabro-cli/src/main.rs` | Modify — add Command variants, delete detach_run() |\n\n## Verification\n\n1. `cargo build --workspace` — compiles\n2. `cargo test --workspace` — all existing + new tests pass\n3. `cargo clippy --workspace -- -D warnings` — clean\n4. Manual: `fabro create <workflow> --goal \"test\"` → prints run ID, creates spec.json in run dir\n5. Manual: `fabro start <run_id>` → spawns engine, status transitions\n6. Manual: `fabro attach <run_id>` → live progress with spinners, exits when done with correct exit code\n7. Manual: `fabro run <workflow>` → identical UX to current foreground behavior\n8. Manual: `fabro run -d <workflow>` → prints run ID, background process runs\n9. Manual: Ctrl+C during `fabro run` kills child; Ctrl+C during `fabro attach` detaches\n10. Manual: workflow with human gate — `fabro run` shows interactive prompt, answer flows back to engine\n\n",
+    "failure_signature": "",
+    "failure_class": "",
+    "internal.run_id": "01KM4DKAWADPG0HY3PZCGQJ7H2",
+    "current_node": "toolchain",
+    "internal.retry_count.start": 1,
+    "internal.thread_id": "start",
+    "internal.retry_count.toolchain": 1,
+    "command.stderr": "",
+    "command.output": "cargo 1.94.0 (85eff7c80 2026-01-15)\n",
+    "graph.model_stylesheet": "\n            * { backend: api; model: claude-opus-4-6;}\n        ",
+    "graph.rankdir": "LR",
+    "internal.fidelity": "compact",
+    "graph.goal": "# Decompose `fabro run` into `create` / `start` / `attach`\n\n## Context\n\n`fabro run` currently does everything in a single process: creates the run directory, sets up the event system, builds the sandbox, runs the workflow engine, writes the conclusion, and renders live progress. The `--detach` flag is a bolt-on that spawns a child process by reconstructing CLI argv — brittle and not composable.\n\nThe goal is to decompose into three primitives (Docker-style):\n- **`fabro create`** — allocate run, persist spec, return run ID\n- **`fabro start`** — spawn a detached engine process (always a separate process)\n- **`fabro attach`** — tail progress.jsonl with live rendering + handle interviews\n\nCompositions:\n- `fabro run` = create + start + attach (attach opens the file before start, guaranteeing zero missed events)\n- `fabro run --detach` = create + start + print run ID\n- Standalone `fabro attach <id>` = reconnect to any running/finished run\n\n## Key design decisions\n\n### 1. Attach absorbs `run_progress.rs`\nThe existing `ProgressUI` (indicatif spinners, stage tracking, tool call rendering) moves into `attach`. Rather than building a new renderer, we add a `handle_json_line(&str)` method to ProgressUI that parses JSONL envelopes and dispatches to the same internal rendering methods (`on_stage_started`, `finish_stage`, `on_tool_call_started`, etc.). This preserves 100% rendering fidelity.\n\nThe dispatch pattern already exists in `format_event_pretty()` in `logs.rs` — match on the `\"event\"` string field, extract typed values from JSON. The internal ProgressUI methods already take simple types (strings, ints), not `WorkflowRunEvent`.\n\n`handle_event(&WorkflowRunEvent)` stays for any in-process callers (API server).\n\n### 2. File-based interview IPC\nThe engine process uses a new `FileInterviewer` (impl Interviewer) that:\n- Writes `interview_request.json` (serialized `Question`) to run_dir\n- Polls for `interview_response.json` in run_dir\n- Deserializes the `Answer`, cleans up both files\n\nThe attach loop watches for `interview_request.json`:\n1. Hides indicatif bars (same as `ProgressAwareInterviewer` does today)\n2. Prompts user via `ConsoleInterviewer` logic\n3. Writes `interview_response.json`\n4. Shows bars again\n\n`Question` and `Answer` already derive `Serialize`/`Deserialize`.\n\n### 3. RunSpec persistence\n`create` writes `spec.json` to run_dir — a serializable struct with all CLI args needed to run the engine. Replaces the argv-reconstruction in `detach_run()`.\n\n### 4. Engine invocation\n`start` spawns `fabro _run_engine --run-dir <dir>` — a hidden internal command that reads `spec.json` and executes the workflow. The child uses `FileInterviewer` instead of `ConsoleInterviewer`.\n\n### 5. Stdin and Ctrl+C\n- `fabro run` (foreground): Ctrl+C sends SIGTERM to child (via `run.pid`), waits for conclusion, then exits\n- `fabro attach` (standalone): Ctrl+C just detaches, run continues\n- Engine process stdin is always `/dev/null` — interviews go through file-based IPC, not stdin\n\n---\n\n## Implementation plan\n\n### Phase 1: Foundation — RunSpec + extract engine\n\n**Step 1: RunSpec struct**\n- New file: `lib/crates/fabro-workflows/src/run_spec.rs`\n- `#[derive(Serialize, Deserialize)]` struct: run_id, workflow_path (absolute), dot_source, working_directory, goal, model, provider, sandbox_provider, labels, verbose, no_retro, ssh, preserve_sandbox, dry_run, auto_approve, resume, run_branch\n- Methods: `save(run_dir)`, `load(run_dir)`\n- Register in `lib/crates/fabro-workflows/src/lib.rs`\n\n**Step 2: FileInterviewer**\n- New file: `lib/crates/fabro-interview/src/file.rs`\n- `FileInterviewer { run_dir: PathBuf }` implementing `Interviewer`\n- `ask()`: write `interview_request.json`, poll for `interview_response.json` (100ms interval, respect timeout from Question), deserialize Answer, clean up files\n- Register in `lib/crates/fabro-interview/src/lib.rs`\n\n**Step 3: Extract `run_engine()` from `run_command()`**\n- Modify: `lib/crates/fabro-cli/src/commands/run.rs`\n- New function: `run_engine(spec, run_dir, run_defaults, styles, github_app, git_author) -> Result<()>`\n- Contains lines ~629–end of current `run_command()`: EventEmitter + JSONL writer + cost accumulator + git SHA tracker, sandbox creation, engine execution, conclusion writing, retro, PR creation, cleanup\n- Does NOT register ProgressUI — only writes progress.jsonl\n- Uses `FileInterviewer` instead of `ConsoleInterviewer`/`ProgressAwareInterviewer`\n\n**Step 4: Hidden `_run_engine` command**\n- Modify: `lib/crates/fabro-cli/src/main.rs`\n- Add `_RunEngine { run_dir: PathBuf }` to `Command` enum (hidden)\n- Handler: load `spec.json`, load cli_config/github_app/git_author, call `run_engine()`\n\n### Phase 2: Attach — ProgressUI from JSONL + interview handling\n\n**Step 5: Add `handle_json_line` to ProgressUI**\n- Modify: `lib/crates/fabro-cli/src/commands/run_progress.rs`\n- New method: `handle_json_line(&mut self, line: &str)` that parses envelope JSON and dispatches to existing internal methods:\n  - `\"Sandbox.Initializing\"` / `\"Sandbox.Ready\"` → `on_sandbox_event()`\n  - `\"SetupStarted\"` / `\"SetupCompleted\"` → `on_setup_started/completed()`\n  - `\"StageStarted\"` → `on_stage_started(node_id, name, script)`\n  - `\"StageCompleted\"` → extract fields, call `finish_stage()`\n  - `\"StageFailed\"` → `finish_stage()` + error info\n  - `\"Agent.ToolCallStarted\"` / `\"Agent.ToolCallCompleted\"` → `on_tool_call_started/completed()`\n  - `\"Agent.AssistantMessage\"` → update stage model display\n  - `\"Agent.CompactionCompleted\"` → compaction bar\n  - `\"ParallelBranchStarted\"` / `\"ParallelBranchCompleted\"` → branch tracking\n  - `\"RetroStarted\"` / `\"RetroCompleted\"` / `\"RetroFailed\"` → retro spinner\n  - `\"SshAccessReady\"` → SSH command display\n  - etc.\n- Follows the same pattern as `format_event_pretty()` in `logs.rs` but calls internal rendering methods instead of formatting strings\n\n**Step 6: Attach command**\n- New file: `lib/crates/fabro-cli/src/commands/attach.rs`\n- `attach_run(run_dir, kill_on_detach: bool) -> Result<ExitCode>`:\n  1. Read `spec.json` for header info (run_id, workflow name)\n  2. Create ProgressUI, show header (version, run_id, time, run_dir)\n  3. Poll loop (100ms):\n     - Read new lines from `progress.jsonl`, feed to `progress_ui.handle_json_line()`\n     - Check for `interview_request.json` → hide bars, prompt via ConsoleInterviewer, write `interview_response.json`, show bars\n     - Exit when `conclusion.json` exists and no new lines\n  4. Read `conclusion.json` for exit code: Success/PartialSuccess → 0, else → 1\n- Ctrl+C: if `kill_on_detach`, SIGTERM to child PID from `run.pid`; otherwise print \"Detached\" and exit 0\n- Add `Attach { run: String, verbose: bool }` to `Command` enum\n- Handler: `run_lookup::resolve_run()`, call `attach_run()`\n\n### Phase 3: Create + Start commands\n\n**Step 7: Create command**\n- New file: `lib/crates/fabro-cli/src/commands/create.rs`\n- `create_run(args, run_defaults, styles) -> Result<(String, PathBuf)>`:\n  - Extract lines ~440–627 from `run_command()`: resolve workflow, parse graph, validate, resolve sandbox/model/provider, create run_dir, write graph.fabro/id.txt/status.json(Submitted)/spec.json\n  - Returns (run_id, run_dir)\n- Add `Create` variant to `Command` enum (same args as RunArgs minus --detach/--run-id/--run-dir)\n\n**Step 8: Start command**\n- New file: `lib/crates/fabro-cli/src/commands/start.rs`\n- `start_run(run_dir, inherit_stdin: bool) -> Result<u32>` (returns child PID):\n  - Validate status.json is `Submitted`\n  - Spawn `fabro _run_engine --run-dir <dir>` as detached child (setsid, stdout/stderr → detach.log, stdin → /dev/null)\n  - Write child PID to `run.pid`\n  - Return PID\n- Add `Start { run: String }` to `Command` enum\n- Handler: resolve run, call `start_run()`\n\n### Phase 4: Recompose `fabro run`\n\n**Step 9: Rewrite `run_command()` as composition**\n- `fabro run` (foreground):\n  ```\n  let (run_id, run_dir) = create_run(args, ...)?;\n  let _child_pid = start_run(&run_dir)?;\n  let exit_code = attach_run(&run_dir, kill_on_detach=true)?;\n  std::process::exit(exit_code);\n  ```\n- `fabro run --detach`:\n  ```\n  let (run_id, run_dir) = create_run(args, ...)?;\n  start_run(&run_dir)?;\n  println!(\"{run_id}\");\n  ```\n- Delete `detach_run()` from main.rs\n- Deprecate `--run-id` / `--run-dir` hidden flags\n\n### Phase 5: Cleanup + testing\n\n**Step 10: Tests**\n- `run_spec.rs`: save/load roundtrip\n- `file.rs` (FileInterviewer): write request → write response → verify ask() returns correct answer\n- `run_progress.rs`: test `handle_json_line` with sample JSONL lines (stage started/completed, tool calls, etc.)\n- `attach.rs`: integration test — write JSONL lines to a temp file, verify attach loop renders and exits correctly\n- Existing tests remain unchanged\n\n**Step 11: Remove dead code**\n- Delete `detach_run()` from main.rs\n- Remove `--run-id` / `--run-dir` args from RunArgs\n- `ProgressAwareInterviewer` moves into attach.rs (or gets deleted if attach handles the coordination directly)\n\n---\n\n## Files summary\n\n| File | Action |\n|------|--------|\n| `lib/crates/fabro-workflows/src/run_spec.rs` | **New** — RunSpec struct |\n| `lib/crates/fabro-workflows/src/lib.rs` | Modify — register run_spec module |\n| `lib/crates/fabro-interview/src/file.rs` | **New** — FileInterviewer |\n| `lib/crates/fabro-interview/src/lib.rs` | Modify — register file module |\n| `lib/crates/fabro-cli/src/commands/create.rs` | **New** — create logic extracted from run.rs |\n| `lib/crates/fabro-cli/src/commands/start.rs` | **New** — spawn detached engine process |\n| `lib/crates/fabro-cli/src/commands/attach.rs` | **New** — attach loop + interview handling |\n| `lib/crates/fabro-cli/src/commands/run_progress.rs` | Modify — add `handle_json_line()` method |\n| `lib/crates/fabro-cli/src/commands/run.rs` | Modify — extract run_engine(), rewrite run_command() as composition |\n| `lib/crates/fabro-cli/src/commands/mod.rs` | Modify — register new modules |\n| `lib/crates/fabro-cli/src/main.rs` | Modify — add Command variants, delete detach_run() |\n\n## Verification\n\n1. `cargo build --workspace` — compiles\n2. `cargo test --workspace` — all existing + new tests pass\n3. `cargo clippy --workspace -- -D warnings` — clean\n4. Manual: `fabro create <workflow> --goal \"test\"` → prints run ID, creates spec.json in run dir\n5. Manual: `fabro start <run_id>` → spawns engine, status transitions\n6. Manual: `fabro attach <run_id>` → live progress with spinners, exits when done with correct exit code\n7. Manual: `fabro run <workflow>` → identical UX to current foreground behavior\n8. Manual: `fabro run -d <workflow>` → prints run ID, background process runs\n9. Manual: Ctrl+C during `fabro run` kills child; Ctrl+C during `fabro attach` detaches\n10. Manual: workflow with human gate — `fabro run` shows interactive prompt, answer flows back to engine\n"
+  },
+  "logs": [],
+  "node_outcomes": {
+    "toolchain": {
+      "status": "success",
+      "context_updates": {
+        "command.stderr": "",
+        "command.output": "cargo 1.94.0 (85eff7c80 2026-01-15)\n"
+      },
+      "notes": "Script completed: command -v cargo >/dev/null || { curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -s -- -y && sudo ln -sf $HOME/.cargo/bin/* /usr/local/bin/; }; cargo --version 2>&1",
+      "duration_ms": 109
+    },
+    "start": {
+      "status": "success",
+      "duration_ms": 0
+    }
+  },
+  "next_node_id": "preflight_compile",
+  "node_visits": {
+    "toolchain": 1,
+    "start": 1
+  }
+}
\ No newline at end of file
diff --git a/nodes/start/status.json b/nodes/start/status.json
new file mode 100644
index 000000000..769778b4d
--- /dev/null
+++ b/nodes/start/status.json
@@ -0,0 +1,6 @@
+{
+  "status": "success",
+  "notes": null,
+  "failure_reason": null,
+  "timestamp": "2026-03-20T01:26:22.969161+00:00"
+}
\ No newline at end of file
diff --git a/nodes/toolchain/script_invocation.json b/nodes/toolchain/script_invocation.json
new file mode 100644
index 000000000..d68c414c4
--- /dev/null
+++ b/nodes/toolchain/script_invocation.json
@@ -0,0 +1,5 @@
+{
+  "command": "command -v cargo >/dev/null || { curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -s -- -y && sudo ln -sf $HOME/.cargo/bin/* /usr/local/bin/; }; cargo --version 2>&1",
+  "language": "shell",
+  "timeout_ms": null
+}
\ No newline at end of file
diff --git a/nodes/toolchain/script_timing.json b/nodes/toolchain/script_timing.json
new file mode 100644
index 000000000..d62fa29f1
--- /dev/null
+++ b/nodes/toolchain/script_timing.json
@@ -0,0 +1,5 @@
+{
+  "duration_ms": 108,
+  "exit_code": 0,
+  "timed_out": false
+}
\ No newline at end of file
diff --git a/nodes/toolchain/status.json b/nodes/toolchain/status.json
new file mode 100644
index 000000000..b881689a5
--- /dev/null
+++ b/nodes/toolchain/status.json
@@ -0,0 +1,6 @@
+{
+  "status": "success",
+  "notes": "Script completed: command -v cargo >/dev/null || { curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -s -- -y && sudo ln -sf $HOME/.cargo/bin/* /usr/local/bin/; }; cargo --version 2>&1",
+  "failure_reason": null,
+  "timestamp": "2026-03-20T01:26:23.087261+00:00"
+}
\ No newline at end of file