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+# Action Space
+
+Inventory of user interaction primitives Sanderling currently supports, compared against the full set available through the Maestro driver layer.
+
+## Current Actions
+
+| Action | Parameters | Notes |
+|--------|-----------|-------|
+| `Tap` | `on` (selector or element) | Single tap on element or coordinates |
+| `DoubleTap` | `on` (selector or element) | Two taps within a sub-100 ms window |
+| `LongPress` | `on` (selector or element) | Press and hold; resolves to coordinates |
+| `InputText` | `into`, `text` | Type into focused field |
+| `Swipe` | `from`, `to`, `durationMillis?` | Point-to-point or element-to-element |
+| `Scroll` | `direction`, `in?`, `durationMillis?` | Scroll a container up, down, left, or right |
+| `PressKey` | `key` | back, home, enter, tab, up, down, left, right |
+| `Wait` | `durationMillis` | Sleep for N ms |
+
+## Gaps vs Maestro Driver
+
+The Maestro driver layer (both `AndroidDriver` and `IOSDriver`) already implements these actions. They are not yet surfaced in Sanderling's action model.
+
+### User Interaction Gaps
+
+| Action | Priority | Notes |
+|--------|----------|-------|
+| `EraseText` | Medium | Clear N characters from focused field |
+| `HideKeyboard` | Medium | Dismiss software keyboard after text input |
+| `PasteText` | Low | Paste clipboard content into focused field |
+
+### Device/Environment Gaps
+
+These are less about user gesture modeling and more about test environment setup. Separate decision on whether they belong in the action model.
+
+| Action | Notes |
+|--------|-------|
+| `SetLocation` | GPS coordinate mocking |
+| `SetOrientation` | Portrait, landscape-left, landscape-right |
+| `SetAirplaneMode` | Network condition simulation |
+| `OpenLink` | Deep links and URLs |
+| `AddMedia` | Inject photos or videos into device gallery |
+
+### Out of Scope
+
+These Maestro commands don't fit Sanderling's interaction model:
+
+- `LaunchApp`, `StopApp`, `KillApp`, `ClearState` - app lifecycle, handled outside the action stream
+- `AssertVisible`, `AssertWithAI` - Sanderling has its own property and assertion model
+- `RunScript`, `EvalScript`, `RunFlow`, `Repeat` - Sanderling has its own flow and generator model
+- `InputRandomText/Number/Email/...` - Sanderling's `from()` and `weighted()` generators cover this