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+---
+name: org-window-habit
+description: Edit Org-mode data for org-window-habit safely. Use when creating or changing window-based habits, CONFIG or OWH_CONFIG properties, completion windows, versioned habit requirements, reset/start dates, or dated pauses and resumptions in .org files. Preserve Org history and repository-specific property-prefix conventions. Do not use for ordinary org-habit entries that have no window-habit configuration.
+---
+
+# Org Window Habit
+
+Edit habit data without requiring the package source repository to be the current workspace. Focus on the target Org heading and its configuration history; do not reproduce the human README.
+
+## Inspect before editing
+
+1. Locate the exact heading and read the whole entry, including planning timestamps, property drawer, logbook, and state history.
+2. Determine the configured property prefix from nearby window habits. The unified property may be `CONFIG`, `OWH_CONFIG`, or another prefixed form. Preserve the local convention.
+3. Preserve unrelated properties, IDs, scheduling timestamps, log entries, heading state, and file formatting unless the request requires changing them.
+4. Prefer the unified `CONFIG` property when creating new data. Do not migrate legacy scattered properties merely because they exist.
+
+## Maintain a valid habit entry
+
+For a new active habit, provide:
+
+- a TODO heading;
+- a `SCHEDULED` or `DEADLINE` timestamp with any repeater;
+- `STYLE` set to `habit` when that is the repository convention;
+- a unified config containing `:window-specs`; and
+- TODO-state logging so completions appear in the state history.
+
+Use a bare plist for one configuration:
+
+```org
+:CONFIG: (:window-specs ((:duration (:days 7) :repetitions 3)) :assessment-interval (:days 1))
+```
+
+Use a list of plists for versioned configurations. Put the most recent version first. Every version is a complete configuration, not a patch: retain `:window-specs` and copy any other parameters that should continue to apply.
+
+## Apply `:from` and `:until` precisely
+
+Treat each version as the half-open interval `[from, until)` in local time:
+
+- `:from` is inclusive. The version applies at midnight on that date.
+- `:until` is exclusive. The version no longer applies at midnight on that date.
+- Missing `:from` means unbounded past.
+- Missing `:until` means unbounded future.
+- A lone `:from` on a single config starts or resets the habit and ignores earlier completions; it does not represent a pause.
+
+Accepted date values include ISO strings and Org timestamps. Preserve the file's style, normally `"YYYY-MM-DD"` or `"[YYYY-MM-DD Day]"`. Because dates normalize to midnight, use the following day when the user means “through the end of this date.”
+
+For a continuous rule change, pair the newer version's `:from` with the older version's `:until` at the same date:
+
+```org
+:CONFIG: ((:from "2026-06-01" :window-specs ((:duration (:days 7) :repetitions 5))) (:until "2026-06-01" :window-specs ((:duration (:days 7) :repetitions 3))))
+```
+
+The parser can infer the newer `:from` from an adjacent older `:until` in simple chains, but write both sides when editing data directly. Explicit boundaries make pauses and later edits unambiguous.
+
+Avoid overlaps. A later version must not start before the preceding version ends. Do not put `:from` on the older version to describe the start of a forward pause; that bounds the older version's beginning instead.
+
+## Pause and resume habits
+
+Pause an active single-config habit at date `P` by adding `:until P`. The old configuration remains as history and no configuration is active at or after `P`:
+
+```org
+:CONFIG: (:window-specs ((:duration (:days 7) :repetitions 2)) :until "2026-05-21")
+```
+
+Pause the current version of an already-versioned habit by adding `:until P` to its first plist. Do not discard older versions.
+
+Resume at date `R` by prepending or restoring a complete newest config with `:from R`, while retaining `:until P` on the previously active config:
+
+```org
+:CONFIG: ((:from "2026-08-09" :window-specs ((:duration (:days 7) :repetitions 2))) (:until "2026-05-21" :window-specs ((:duration (:days 7) :repetitions 2))))
+```
+
+The habit is inactive throughout `[P, R)`. If requirements change on resume, change only the new first plist and preserve the historical plist verbatim.
+
+Do not treat `STYLE: habit-paused`, removing a repeater, or changing the TODO keyword as equivalent to a dated config pause. Those may hide or disable an entry under local Org conventions, but they do not record an inactive interval for window-habit history. If the repository intentionally uses one of those mechanisms in addition to config dates, preserve that convention and still encode the hiatus with `:until`/`:from` when historical scoring matters.
+
+## Verify the edit
+
+1. Re-read the complete property value and check balanced parentheses and quoting.
+2. Confirm version order is newest first and every version contains `:window-specs`.
+3. Confirm continuous boundaries are equal, pauses satisfy `until < from`, and no ranges overlap.
+4. Confirm a pause date matches midnight semantics; adjust by one day if the user meant the end of a day.
+5. Review the diff and ensure no logbook entries or unrelated Org data changed.
+6. When the package repository and Nix environment are available, run the narrow ERT/config checks or `just test` for behavior changes. For data-only edits, syntax and diff review are normally sufficient.
diff --git a/.agents/skills/org-window-habit/agents/openai.yaml b/.agents/skills/org-window-habit/agents/openai.yaml
new file mode 100644
index 0000000..abdc356
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+++ b/.agents/skills/org-window-habit/agents/openai.yaml
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+interface:
+  display_name: "Org Window Habit"
+  short_description: "Edit and pause window-based Org habits"
+  default_prompt: "Use $org-window-habit to update this habit while preserving its configuration history."