Flow reports rendered every step flat, hiding which steps ran inside a
`when:` block or a `run:` fragment. The tool-server now stamps
`StepReport.depth` (+1 per block directive, omitted at top level) and
the CLI/MCP renderers indent step labels and under-step lines by it:
```
✓ 1 launch
✓ 2 when visible "What's new" — condition met
✓ 3 tap "Skip"
✓ 4 run dismiss [dismiss]
✓ 5 tap "OK" [dismiss]
```
Invariants:
- **Wire-compatible both ways** — a flow with no block directives
reports byte-identical to the pre-depth shape; a pre-depth server
renders flat as before.
- **Skipped ≡ entered** — skipped/errored/aborted blocks report the same
depths as entered ones, keeping reports comparable run-to-run.
- **Untrusted wire data** — renderers clamp depth (display cap, not a
producer bound): hostile values render flat or at the cap, never throw
or allocate huge strings.
Also fixes a pre-existing bug: under-step warning/artifact lines now
stay aligned past 99 steps.
Tests pin depth on every producer path (entered/skipped/errored/aborted
blocks, `run:` success/failure markers, `run:`-in-`when:`) and renderer
alignment incl. the clamp boundary.
Co-authored-by: Claude Fable 5 <noreply@anthropic.com>
## What
A `when:` block runs a step list only when one condition holds — a UI
condition (`exists`/`visible`/`hidden`/`text`, the await/assert shapes)
or a static `platform` test. **No else**, by design: a block exists to
restore determinism (dismiss an interstitial, reconverge), never to
test two paths. Tap-if-present is a one-step block:
`when: { visible: "Got it" }` + `steps: [tap: "Got it"]`.
No per-step `optional:` — `when:` covers every directive once. The key
is rejected at parse with a pointer to `when:`, not silently dropped (a
Maestro habit that would leave a "can't fail" step hard-stopping the
flow).
## How
- The guard reuses the assert engine at the 1s grace (`timeout` is a
parse error), so a skipped block barely costs a clean run.
- Verdicts are evidence-based: no trustworthy read in the window →
indeterminate → the step **errors** ("could not evaluate" is not
"condition false"); a transient read failure after trusted reads showed
the condition false stays a clean skip.
- `platform` folds `ios-remote` into `ios` — the parser rejects that
spelling, so the fold is the only way a guard matches a remote sim.
- A skipped block reports one line per authored step, same shape for
unmet guard, hard stop, or cancellation; everything goes through
`pushReport`, so when lines stream live. Failures inside an entered
block hard-stop as usual.
- Results carry an explicit `aborted` flag; `ok` keys off
fail/error/cancel, not skip lines.
- Nesting is capped at 20, so a cyclic YAML alias is a structured parse
error, not a stack overflow.
## Testing
`vitest` 2546 pass (17 when-specific); `tsc --noEmit` (tool-server,
argent-mcp, argent-cli), eslint, prettier clean.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
---------
Co-authored-by: Claude Fable 5 <noreply@anthropic.com>
Jakub Piasecki