diff --git a/docs-ai/063-agent-workflows/000-plan.md b/docs-ai/063-agent-workflows/000-plan.md
index 2b861bb67..c2e514055 100644
--- a/docs-ai/063-agent-workflows/000-plan.md
+++ b/docs-ai/063-agent-workflows/000-plan.md
@@ -2,7 +2,7 @@
 
 | | |
 | --- | --- |
-| **Status** | In progress — R1 shipped in v2026.8.29; R2a under way: B1 (#740, [006](006-b1-definitions.md)), #733 (#741), #726 T0 (#739), and B2 (#743, [007](007-b2-runner-core.md)) merged; B3 runner wiring = #744 (review; record [008](008-b3-runner-wiring.md)) |
+| **Status** | In progress — R1 shipped in v2026.8.29; R2a under way: B1 (#740, [006](006-b1-definitions.md)), #733 (#741), #726 T0 (#739), B2 (#743, [007](007-b2-runner-core.md)), and B3 (#744, [008](008-b3-runner-wiring.md)) merged; C1 is next |
 | **Anchor date** | 2026-08-21 |
 | **Primary PRs** | R1: #709 (C0), #710 (A1), #713 (A1b), #714 (A2) — shipped in v2026.8.29; R2a: #740 (B1), #743 (B2, [007](007-b2-runner-core.md)); #744 (B3, [008](008-b3-runner-wiring.md)); C1–D3 TBD |
 | **Related** | [047 cross-agent-handoff](../047-cross-agent-handoff/000-plan.md), [049 agents-toolbar-entry](../049-agents-toolbar-entry/000-plan.md), [053 agent-profiles](../053-agent-profiles/000-plan.md), [055 agent-profile-runtimes](../055-agent-profile-runtimes/000-plan.md), [059 agent-transcript-snapshots](../059-agent-transcript-snapshots/000-plan.md), [060 cli-targeting-and-contract-governance](../060-prowl-cli-targeting-and-contract-governance/000-plan.md), [061 native-toolbar-controls](../061-native-toolbar-controls/toolbar-controls.md), [064 agent-completion-signals](../064-agent-completion-signals/000-plan.md) (signal bus, `agents signal` / `agents wait`), [#699 `prowl create pane`](https://github.com/onevcat/Prowl/issues/699), [PR #651 (direction reference, not merged)](https://github.com/onevcat/Prowl/pull/651), [DSL spec (living)](dsl-spec.md), [release plan (living)](release-plan.md), `docs/components/handoff.md`, `docs/components/agent-profiles.md`, `docs/components/cli.md` |
@@ -596,6 +596,15 @@ attaches hooks through A2's launch boundary.
 
 ## Amendments
 
+- Updated 2026-08-30: a two-round display-sleep spike located the `CREATE_FAILED` cause in the
+  pinned GhosttyKit, not in Prowl's launch ordering: with zero active displays the renderer's
+  eager CoreVideo display link (`window-vsync = true`) aborts `ghostty_surface_new`, while
+  `window-vsync = false` — even toggled at runtime — creates fully working tabs, splits, and
+  Profile panes that render normally after wake. #746 implements upstream Ghostty's #13639 fix
+  in the fork, so neither a Prowl-side display override nor the headless-or-fail workflow policy
+  remains planned; honest rollback for otherwise unknown tab/split creation failures remains
+  optional generic hardening — see
+  [009-display-sleep-surface-spike.md](009-display-sleep-surface-spike.md).
 - Updated 2026-08-29 (B2, grilled): the runner core is a pure reducer (`WorkflowRunMachine`)
   whose effects B3 interprets; activation tokens are checked in the machine, the dispatch store
   stays untouched; the watchdog observes each activation through `observeAgentDispatch` +
diff --git a/docs-ai/063-agent-workflows/009-display-sleep-surface-spike.md b/docs-ai/063-agent-workflows/009-display-sleep-surface-spike.md
new file mode 100644
index 000000000..e1c3354a8
--- /dev/null
+++ b/docs-ai/063-agent-workflows/009-display-sleep-surface-spike.md
@@ -0,0 +1,263 @@
+# 063.009 — Display-Sleep Surface Creation Spike
+
+## Status
+
+Accepted investigation, 2026-08-30, in two rounds against `main` at `299b5a5d` (includes
+[#744](https://github.com/onevcat/Prowl/pull/744)). Neither round changed production code:
+every experimental edit was reverted after the result was established.
+
+The first round concluded that no Ghostty surface can be created while the display is asleep
+and recommended a headless fallback. The second round re-verified that claim and **falsified
+it**: surface creation only fails because the pinned GhosttyKit makes a CoreVideo display link
+a hard precondition of renderer initialization, and Ghostty already exposes the switch
+(`window-vsync`) that removes that precondition. Upstream Ghostty fixed the same failure on
+2026-08-05. The recommendation below supersedes the first-round one.
+
+This is not an R2a release blocker. The required surface-level fix is implemented in
+[#746](https://github.com/onevcat/Prowl/pull/746), which backports the upstream repair into the
+GhosttyKit fork. No Prowl-side display override or execution-mode substitution remains planned
+for this issue; see [Outcome](#outcome).
+
+## Problem summary
+
+Long-running agent work commonly continues while the Mac display is asleep. In that state, a
+CLI-driven Agent Profile launch fails with `CREATE_FAILED`:
+
+> The terminal surface for Agent Profile “…” could not be created.
+
+The unified log shows the native cause:
+
+```text
+CVDisplayLinkCreateWithCGDisplays error -6661 due to invalid display count (0)
+com.mitchellh.ghostty:embedded_window: error initializing surface err=error.OutOfMemory
+```
+
+`pmset -g log` shows `Display is turned off`; waking the display makes the same launch succeed.
+The question for both rounds:
+
+> Can Prowl preserve an interactive launch by changing when or how it creates and attaches the
+> Ghostty surface while the display remains asleep?
+
+## Current launch boundary
+
+An Agent Profile launch intentionally stages the Swift-side tab/split with
+`defersSurfaceCreation: true`, registers the managed signal channel through
+`onAgentProfileSurfacePrepared`, and then calls `GhosttySurfaceView.armSurfaceCreation()`.
+Failure rolls the tab or split back and becomes `.surfaceCreationFailed`.
+
+This ordering is required for managed hooks: the launch-scoped environment must be prepared
+before the child process starts. It also makes the Profile path honest about native creation
+failure.
+
+Ordinary tab and split creation use the immediate `GhosttySurfaceView` initializer instead. The
+initializer calls `armSurfaceCreation()` but discards its Boolean result. Consequently, the
+Swift-side tab or split can be returned even when `ghostty_surface_new` returned `nil`. A visible
+tab UUID is therefore not evidence that a working terminal surface exists.
+
+Relevant boundaries:
+
+- `supacode/Infrastructure/Ghostty/GhosttySurfaceView.swift`
+- `supacode/Infrastructure/Ghostty/GhosttyRuntime.swift` (`loadConfig`, `reloadConfig`,
+  `loadTerminalProgramOverrides`, the `screensDidSleep`/`screensDidWake` observers)
+- `supacode/Features/Terminal/Models/WorktreeTerminalState.swift`
+- `supacode/App/WorkflowRuntimeComposition.swift`
+- `ThirdParty/ghostty/src/renderer/generic.zig`, `ThirdParty/ghostty/pkg/macos/video/display_link.zig`
+
+## Method
+
+Both rounds used a separately launched Debug app with a scratch `CFFIXED_USER_HOME`, a scratch
+Git repository seeded through `~/.prowl/repository-entries.json`, a hand-written Codex Profile in
+`~/.prowl/global.onevcat.json`, and a dedicated `PROWL_CLI_SOCKET`; the installed Prowl instance
+and its sessions were not touched. Display state was driven with `pmset displaysleepnow` and
+verified from `pmset -g log`; a `caffeinate -u -t 3` wake trap restored the display after each
+bounded attempt. Attempts that did not stay inside the logged display-off interval were discarded.
+
+The second round additionally ran a one-second CoreGraphics/CoreVideo probe during every
+display-off interval so each result is paired with the display state Ghostty actually saw:
+
+```text
+active=0 online=2 main=2 mainAsleep=1 mainActive=0 screens=2 cv[active=-6661 main=0]
+```
+
+`CGGetActiveDisplayList` reports zero displays while both displays stay online and
+`NSScreen.screens` still lists them. `CVDisplayLinkCreateWithActiveCGDisplays` fails with
+`kCVReturnInvalidDisplay` (-6661); `CVDisplayLinkCreateWithCGDisplay(CGMainDisplayID())` still
+succeeds. Every pane's health was checked from inside the display-off interval with
+`prowl send … --capture` (a dead shell times out with `WAIT_TIMEOUT`), and again after wake.
+
+## Round 1 experiments (Swift-side ordering)
+
+Experimental code lived temporarily on `spike/profile-launch-display-sleep` and was deleted.
+
+| Experiment | Result | Interpretation |
+| --- | --- | --- |
+| Baseline Profile launch with the display awake | Succeeded | The current #744/Profile/CLI wiring is functional under its normal display precondition. |
+| Unmodified Profile launch during a stable display-off interval | Failed with `CREATE_FAILED` at native surface creation | Reproduced the known issue on current `main`. |
+| Build the Swift tab/split structure detached, prepare hooks, then attach and arm the surface | Unit test was red before staging and green after it; real tab and split Profile launches still failed while the display was off | Tree attachment and managed-hook ordering are not the cause. |
+| Disable deferred creation and create the native Profile surface during initialization | Failed while the display was off | Deferral itself is not the cause. |
+| Remove Ghostty `initial_input` and attempt post-create text injection | Failed before input could be delivered | Initial input is not the cause. |
+| Remove the Profile launch's `surfaceEnvironment` | Failed while the display was off | Launch-scoped carriers and managed-hook environment are not the cause. |
+| Create ordinary tabs and splits with temporary logging at the native boundary | Swift-side creation returned identifiers, but native Ghostty surface creation failed | These paths ignore the failed arm result and leave a non-functional shell. |
+| Wake the display and repeat the same Profile launch | Succeeded | The failure follows display availability, not #744's workflow wiring or the selected Profile. |
+
+Round 1 correctly established that Swift-side ordering is irrelevant. Its conclusion that “every
+path that ultimately calls `ghostty_surface_new` needs an active display” over-generalized from
+the default configuration; it never varied the Ghostty renderer configuration.
+
+## Round 2: where the precondition actually lives
+
+Reading the pinned GhosttyKit (`onevcat/ghostty` at `48365577c`, v1.3.1 plus four fork patches):
+
+- `pkg/macos/video/display_link.zig` — `createWithActiveCGDisplays()` maps **any**
+  `CVDisplayLinkCreateWithActiveCGDisplays` failure to `error.OutOfMemory`. The logged
+  “OutOfMemory” is this mapping, not memory pressure.
+- `src/renderer/generic.zig` (`init`) — `if (options.config.vsync) try
+  DisplayLink.createWithActiveCGDisplays() else null`. With `window-vsync = true` (the default)
+  the `try` aborts renderer initialization, which aborts `ghostty_surface_new`. With
+  `window-vsync = false` no display link is created and the renderer runs in its existing
+  change-driven mode (`hasVsync()` returns false; `renderer.Thread` draws after each render and
+  on its 8 ms animation timer). Every other use of `display_link` is already `orelse`-guarded.
+- `src/config/Config.zig` — `window-vsync` is documented as macOS-only and “changing this value
+  at runtime will only affect new terminals”, i.e. the choice is fixed per surface at creation.
+
+Upstream Ghostty removed the precondition in
+[ghostty-org/ghostty#13639](https://github.com/ghostty-org/ghostty/pull/13639) (“macos: tolerate
+display link creation failures”, merged 2026-08-05, commit `a177ba90af`): display link creation
+became lazy and non-fatal (`syncDisplayLink`), retried on the next display-ID update, with
+`CreationFailed` replacing the misleading `OutOfMemory`. Follow-ups
+[#14035](https://github.com/ghostty-org/ghostty/pull/14035) and
+[#14068](https://github.com/ghostty-org/ghostty/pull/14068) (2026-08-26/29) extend the same
+`syncDisplayLink` path so the link is also re-synced from rendering activity. None of these are
+in a tagged release yet (v1.3.1 is the latest tag; `main` is ~2,400 commits ahead of it). The
+patch does not apply cleanly to v1.3.1 because `generic.zig` drifted, but a hand port is about
+70 lines and was prepared on a throwaway submodule branch (`zig fmt` clean, deleted afterwards).
+
+Prowl already has the hook the lazy path needs: `GhosttySurfaceView.windowDidChangeScreen()`
+pushes `ghostty_surface_set_display_id` on `NSWindow.didChangeScreenNotification`, and
+`GhosttyRuntime` observes `screensDidSleep`/`screensDidWake` (currently log-only).
+
+## Round 2 experiments (renderer configuration)
+
+All rows below ran inside logged display-off intervals with the probe reporting `active=0`.
+
+| Experiment | Result | Interpretation |
+| --- | --- | --- |
+| Unmodified app, default `window-vsync`: `send` to a pane created while awake | Worked (`OFF-A-…` captured) | Existing surfaces keep running while the display sleeps; only creation is affected. |
+| Same, `create tab` / `create pane` | Returned identifiers; shells dead (`WAIT_TIMEOUT`), still dead after wake; `READ_FAILED` | Re-confirms round 1: the non-Profile paths hide native failure. |
+| Same, Profile launch | `CREATE_FAILED`, log shows `-6661` then `error.OutOfMemory` | Reproduced. |
+| Unmodified app relaunched with `window-vsync = false` in the scratch `~/.config/ghostty/config`; `create tab`, `create pane`, Profile launch while dark | **All succeeded**; shells answered from inside the dark interval (`OFF-B-…`, `OFF-C-…`); Codex started in the Profile pane; no Ghostty error lines | The display link is the only native precondition. The same GhosttyKit binary creates fully working surfaces without a display. |
+| Wake the display; `send` to those surfaces again; screenshot the window | Worked (`WAKE-B-…`, `WAKE-C-…`); the panes rendered normally | Change-driven rendering is functional after wake, not only while dark. |
+| Default config at launch; flip `window-vsync = false` at runtime via Ghostty's `reload_config` (`prowl key … cmd-shift-comma`); go dark; `create tab` and Profile launch | Both succeeded | `GhosttyRuntime.reloadConfig` → `ghostty_app_update_config` is enough to switch the mode for surfaces created afterwards; no relaunch needed. |
+| Still dark: flip back to `window-vsync = true` via `reload_config`; probe the earlier panes; `create tab` again | Earlier panes unaffected (`OFF-A2-…`, `OFF-B2-…`); the new tab was a dead shell again | The switch is evaluated per surface at creation time and is safe to toggle in both directions while surfaces are live. |
+
+A locally rebuilt GhosttyKit with the ported upstream fix initially could not be tested: `zig build`
+(zig 0.15.2) fails to link its own build runner under Xcode 26.6 (`undefined symbol: _waitpid`,
+`_sigaction`, … — libSystem is not linked). The cause is the SDK, not the cache or `SDKROOT`
+(zig asks `xcrun --sdk macosx --show-sdk-path`, which ignores `SDKROOT`): from SDK 26.4 on,
+`libSystem.tbd` lists `arm64e-macos` instead of `arm64-macos`, and zig 0.15.2's Mach-O linker
+cannot match its `aarch64-macos` target to it (ziglang/zig#31658; fixed on the 0.16 line, never
+released for 0.15). Xcode 26.3 (SDK 26.2) is the last toolchain that works and is now the
+documented requirement in the ghostty fork-sync runbook. Two shortcuts were tried and rejected:
+the leftover Command Line Tools 15.4 SDK links the runner but produces objects whose auto-link
+metadata no longer resolves against the 26.5 SDK, and a patched 26.5 SDK overlay works but is
+not worth maintaining for a toolchain that changes again with the next Ghostty release.
+
+## Conclusion
+
+Surface creation without an active display is possible with the pinned GhosttyKit today, and is
+the default behavior of upstream Ghostty since 2026-08-05. The only native precondition is the
+eager CoreVideo display link that `window-vsync = true` demands; a surface created with
+`window-vsync = false` is a fully working terminal in Ghostty's change-driven rendering mode,
+during display sleep and after wake.
+
+Final decision:
+
+- [#746](https://github.com/onevcat/Prowl/pull/746) resolves display sleep at the Ghostty layer;
+  no display-specific Prowl launch policy is required.
+- “A path that truly works without a display must not create a Ghostty/AppKit terminal
+  surface” is withdrawn. Headless execution is no longer justified by display sleep; the
+  `on_display_unavailable` policy and the `HeadlessAgentExecutor` scope expansion are dropped
+  from this problem's plan (headless stays a V2 topic on its own merits, see
+  [the DSL specification](dsl-spec.md#12-reserved-for-v2)).
+- Honest propagation of an otherwise unknown native surface-creation failure remains useful
+  generic hardening, independent of display sleep and outside the R2a release gate.
+
+## Resolution and residual hardening
+
+### 1. Take the upstream fix into the fork — implemented in #746
+
+The durable fix is upstream #13639: surfaces created without a display get their display link
+lazily once a display is available. [#746](https://github.com/onevcat/Prowl/pull/746)
+backports it onto `onevcat/ghostty` `release/v1.3.1-patched` (`a0671ce9`), rebuilds GhosttyKit
+with Xcode 26.3, and re-pins the prebuilt artifacts. Drop the fork patch when the submodule
+moves to an upstream tag that contains `a177ba90af`.
+
+### 2. Prowl-side `window-vsync` override — not planned
+
+Before the GhosttyKit rebuild succeeded, the viable Prowl-only contingency was to detect zero
+active displays, create the surface with `window-vsync = false`, and restore the user's setting
+afterwards through the existing `GhosttyRuntime.reloadConfig` / `applyConfig` path. The live
+spike proved that mechanism works, but #746 makes it unnecessary and avoids its per-surface
+non-vsync trade-off.
+
+Do not implement this override while the fork carries the upstream fix. If a future Ghostty pin
+regresses, restore or forward-port the upstream behavior first; use this experiment as diagnosis
+and a bounded contingency, not as a standing product fallback.
+
+Zero-code interim for users: `window-vsync = false` in the user's Ghostty config removes the
+failure on a build that does not yet contain #746.
+
+### 3. Make ordinary tab and split creation honest — optional generic hardening
+
+The non-Profile paths currently ignore the `armSurfaceCreation()` result. Independently of
+display sleep, they should eventually roll back the Swift tab/split/target state and return an
+honest failure when `ghostty_surface_new` fails for an unknown reason. Profile launches already
+do this through `.surfaceCreationFailed`.
+
+Do not add a display-specific `DISPLAY_UNAVAILABLE` contract without a reproducible residual
+failure after #746. This hardening is not part of the display-sleep fix or the R2a release gate.
+
+### 4. Workflow semantics
+
+No execution-mode substitution is needed. An interactive role launched while the display sleeps
+is the same Ghostty pane with the same `message` / `repeat` / `focus` / `close` semantics. C1
+needs no display-sleep fallback state.
+
+## Outcome
+
+With the backport in place, the same live protocol (default `window-vsync`, probe `active=0` for
+the whole dark interval) produced the intended result on the rebuilt GhosttyKit: `create tab`,
+`create pane`, and a Profile launch all succeeded while dark and answered from inside the
+interval; the unified log shows `error creating display link; using fallback rendering
+err=error.CreationFailed` for each dark surface and, after wake, `created display link` followed
+by `updating display link display id=2` — Prowl's `windowDidChangeScreen` →
+`ghostty_surface_set_display_id` is the retry trigger, exactly as upstream intended. The
+Prowl-side override is therefore not needed. If a future Ghostty pin regresses, the default
+response is to restore this upstream behavior rather than substitute execution modes or retain
+a parallel Prowl policy.
+
+## Release impact
+
+R2a remains B3 plus C1 as recorded in [the release plan](release-plan.md#r2a--workflow-engine-and-cli).
+Once #746 ships, interactive-workflow verification no longer needs the “keep the display awake”
+caveat. Generic native-failure propagation for ordinary tabs/splits remains optional hardening,
+not display-sleep work and not an R2a requirement.
+
+## Non-goals of this spike
+
+- No production fallback was implemented; the `window-vsync` runs used the user-config and
+  `reload_config` paths only.
+- No virtual-display or screen-wake workaround was attempted.
+- No fallback was proposed for arbitrary launch failures: hook, Profile, credential, renderer,
+  and unknown native failures still fail closed.
+- No Prowl-side fallback was implemented or remains planned; the fork backport made it
+  unnecessary.
+
+## References
+
+- [063.008 — Workflow Runner Wiring (B3)](008-b3-runner-wiring.md)
+- [063 workflow DSL, V2 reservations](dsl-spec.md#12-reserved-for-v2)
+- [064.011 — S3c action, original display-sleep finding](../064-agent-completion-signals/011-s3c-action.md#display-sleep-is-the-create_failed-behind-the-intermittent-profile-launches)
+- [065.005 — K3 settings and verification note](../065-bundled-agent-skills/005-k3-settings-agent-skills.md)
+- [ghostty-org/ghostty#13639 — macos: tolerate display link creation failures](https://github.com/ghostty-org/ghostty/pull/13639)
+- [ghostty-org/ghostty#14035 — renderer: park DisplayLink while idle](https://github.com/ghostty-org/ghostty/pull/14035)
diff --git a/docs-ai/063-agent-workflows/release-plan.md b/docs-ai/063-agent-workflows/release-plan.md
index fc12f6432..98f4fc4bf 100644
--- a/docs-ai/063-agent-workflows/release-plan.md
+++ b/docs-ai/063-agent-workflows/release-plan.md
@@ -29,12 +29,12 @@ user-facing surface may merge before "their" release and stay dormant. Four rele
 R2a, R2b, R3 (R2 was split on 2026-08-29); the [cadence rules](#cadence-and-working-rules)
 say when each is cut:
 
-### Status (2026-08-29)
+### Status (2026-08-30)
 
 | Release | State | Next action |
 | --- | --- | --- |
 | R1 | **Shipped** — v2026.8.29 (2026-08-29) | — |
-| R2a | In progress | B1 #740, #726 T0 #739, #733 #741, and B2 #743 merged; B3 = #744 (review; record [063.008](008-b3-runner-wiring.md)) |
+| R2a | In progress | B1 #740, #726 T0 #739, #733 #741, B2 #743, and B3 #744 merged; C1 is next ([063.008](008-b3-runner-wiring.md), [063.009](009-display-sleep-surface-spike.md)) |
 | R2b | Planned | after R2a ships |
 | R3 | Planned | after R2b ships |