fix(work-items): skip a create-item that duplicates a sibling under the same parent

.changes/work-items/work-resolve-issue-issue-12918-41722155518-1-43b9d454.md

@@ -0,0 +1,7 @@
+---
+bump: patch
+---
+
+### Fixed
+
+- `create-item --parent` in the GitHub and local-markdown adapters no longer files a second child with a title the parent already has ([#12918](https://github.com/melodic-software/claude-code-plugins/issues/12918)): when a child with the same trimmed title is open, or was closed within 24 hours, it creates nothing, exits `0` and prints that child, so a retried or repeated publish files each child once.

plugins/work-items/tools/work-item-tracker/CONTRACT.md

@@ -262,6 +262,19 @@ with one link can both write. An adapter that declares no `add-recurrence` key e
 command substitution, a shape a worktree-isolated session refuses (#6929). `--body` together with
 `--body-file`, or a path that is not a readable, non-empty file, exits `2`.
 
+`create-item --parent <id>` creates nothing when the parent already has a child with the same
+title (exact after trimming leading and trailing whitespace from both) that is open, or
+was closed within the last 24 hours. It then exits `0`, prints that child's normalized item
+object, and names the child on stderr. A child closed earlier does not block a new create. This
+makes a retried or repeated publish of one plan file each child once. Without `--parent`, every
+call creates an item. The check is one read of the parent's children before the write, with no
+compare-and-set, so two calls that run at the same moment can still both create. GitHub reads the
+parent's sub-issues in the target repository with their `closedAt` in one GraphQL query;
+local-markdown reads each child's `closed_at` frontmatter field, which only the file edit that
+closes the item sets (see "local-markdown adapter"), and a closed child without one counts as
+closed earlier. The linear seed does not run the check yet; the gitea seed refuses
+`--parent`.
+
 `label-provenance` answers who applied each named label and whether that person may grant
 admission. For every `--label`, the adapter takes the most recent application of that label
 (GitHub: the latest `labeled` event on the issue timeline by `created_at`), reads the actor's
@@ -888,7 +901,13 @@ network tool (`gh`, `curl`); the conformance suite runs it in CI, offline.
   structured `Blocked by: <id>` body lines; `blocked_by_count` counts blockers whose
   file exists and that are `open`, or `closed` with any non-empty `state_reason` other
   than `completed` (such as `not_planned` or `duplicate`); those closed ones also count
-  in `blocked_by_wont_do_count`. A closed item with no `state_reason` was completed. The lease is the same inline marker used
+  in `blocked_by_wont_do_count`. A closed item with no `state_reason` was completed. An optional
+  `closed_at` field (a UTC ISO-8601 timestamp string) holds when the item was closed, and
+  `create-item`'s sibling check reads it (see "Verbs"). This adapter has no close verb (the seam
+  has none, by design), so no verb writes `state` or `closed_at`: whoever closes an item by
+  editing its file sets `state: "closed"` and, for the sibling check to count the close as
+  recent, `closed_at`. A closed item without `closed_at` counts as closed more than 24 hours
+  ago and never blocks a new create. The lease is the same inline marker used
   everywhere (see "Lease protocol"), appended to the item file.
 - **Identity.** No authenticated provider user exists offline, so `claim` records the
   holder from `git config user.name` (falling back to `$USER`, then `local`) and

plugins/work-items/tools/work-item-tracker/adapters/github/create-item.sh

@@ -88,6 +88,38 @@ fi
 label_list=()
 [[ -z "$labels" ]] || IFS=',' read -ra label_list <<<"$labels"
 
+# Sibling dedupe (CONTRACT.md "Verbs"): a child of the parent in the target repo with the
+# same trimmed title, open or closed within 24 hours, is returned instead of a new issue.
+# One GraphQL read, since the subIssues projection list-sub-items reads has no closedAt.
+# A proxy refusal drops to the REST branch, which refuses --parent.
+if ((native)) && [[ -n "$parent" ]]; then
+  wit_require_github_id "$parent" || wit_usage_error "malformed or non-github --parent id: $parent"
+  # shellcheck disable=SC2016  # GraphQL query: $o/$r/$n are GraphQL variables
+  wit_run_gh_native read api graphql \
+    -f query='query($o:String!,$r:String!,$n:Int!){repository(owner:$o,name:$r){issue(number:$n){subIssues(first:100){nodes{number title state closedAt repository{nameWithOwner}}}}}}' \
+    -f o="$WIT_ID_OWNER" -f r="$WIT_ID_REPO" -F n="$WIT_ID_NUMBER"
+  if (($? == 10)); then
+    native=0
+  else
+    sibling="$(jq -r --arg title "$title" --arg repo "$target_repo" '
+      def trimmed: gsub("^[[:space:]]+|[[:space:]]+$"; "");
+      ($title | trimmed) as $t
+      | [(.data.repository.issue.subIssues.nodes // [])[]
+          | select(((.repository.nameWithOwner // "") | ascii_downcase) == ($repo | ascii_downcase))
+          | select(((.title // "") | trimmed) == $t)
+          | select(.state == "OPEN" or (.closedAt != null
+              and ((.closedAt | sub("\\.[0-9]+"; "") | fromdateiso8601) > now - 86400)))]
+      | (map(select(.state == "OPEN")) + map(select(.state != "OPEN")))[0] // empty
+      | "\(.number) \(.state | ascii_downcase)"' <<<"$WIT_GH_OUT")" || exit "$EX_INTERNAL"
+    if [[ -n "$sibling" ]]; then
+      printf 'create-item: %s already has %s child github:%s#%s titled "%s"; created nothing\n' \
+        "$parent" "${sibling#* }" "$target_repo" "${sibling%% *}" "$title" >&2
+      wit_emit_item "${target_repo%%/*}" "${target_repo##*/}" "${sibling%% *}"
+      exit 0
+    fi
+  fi
+fi
+
 if ((native)); then
   args=(issue create -R "$target_repo" --title "$title" --body "$body")
   [[ -z "$type" ]] || args+=(--type "$type")

plugins/work-items/tools/work-item-tracker/adapters/github/create-item.test.sh

@@ -40,10 +40,19 @@ case "$1 $2" in
   ;;
 "issue view")
   if ((native)); then
-    printf '{"number":42,"title":"t","state":"OPEN","assignees":[],"labels":[{"name":"a"}],"url":"https://github.com/o/r/issues/42"}\n'
+    printf '{"number":%s,"title":"t","state":"OPEN","assignees":[],"labels":[{"name":"a"}],"url":"https://github.com/o/r/issues/%s"}\n' "$3" "$3"
     exit 0
   fi
   ;;
+"api graphql")
+  if ((native)); then
+    no_children='{"data":{"repository":{"issue":{"subIssues":{"nodes":[]}}}}}'
+    printf '%s\n' "${GH_STUB_SUBISSUES:-$no_children}"
+    exit 0
+  fi
+  printf 'HTTP 403: GitHub GraphQL is not available from Claude Code sessions\n' >&2
+  exit 1
+  ;;
 esac
 case "$1" in
 issue | repo)
@@ -131,6 +140,43 @@ EOF
   assert_eq "create-item on gh 2.94 keeps the native path → exit 0" "0" "$rc"
   assert_eq "create-item on gh 2.94 emits id" "github:o/r#42" "$(jq -r '.id' <<<"$OUT")"
   assert_contains "create-item on gh 2.94 calls issue create" "$(<"$STUB/calls.log")" "issue create"
+  assert_not_contains "create-item without --parent reads no sub-issues" "$(<"$STUB/calls.log")" "api graphql"
+
+  # --- sibling dedupe under --parent: open, closed within 24h, closed earlier ---
+  siblings() { # <state> <closedAt or null> <title>
+    printf '{"data":{"repository":{"issue":{"subIssues":{"nodes":[{"number":7,"title":%s,"state":"%s","closedAt":%s,"repository":{"nameWithOwner":"O/R"}}]}}}}}' \
+      "$(jq -cn --arg t "$3" '$t')" "$1" "$2"
+  }
+  hour_ago="\"$(jq -rn 'now - 3600 | todate')\""
+  two_days_ago="\"$(jq -rn 'now - 172800 | todate')\""
+  DEDUPE_ERR="$(mktemp "$TMP_ROOT/f.XXXXXX")"
+
+  OUT="$(GH_STUB_SUBISSUES="$(siblings OPEN null '  T ')" GH_STUB_VERSION=2.94.0 \
+    run_create --title T --parent github:o/r#1 --repo o/r 2>"$DEDUPE_ERR")"
+  rc=$?
+  assert_eq "create-item --parent with an open sibling titled T → exit 0" "0" "$rc"
+  assert_eq "create-item --parent with an open sibling prints its id" "github:o/r#7" "$(jq -r '.id' <<<"$OUT")"
+  assert_not_contains "create-item --parent with an open sibling creates no issue" "$(<"$STUB/calls.log")" "issue create"
+  assert_contains "create-item --parent with an open sibling names it on stderr" "$(<"$DEDUPE_ERR")" "github:o/r#7"
+
+  OUT="$(GH_STUB_SUBISSUES="$(siblings CLOSED "$hour_ago" T)" GH_STUB_VERSION=2.94.0 \
+    run_create --title T --parent github:o/r#1 --repo o/r 2>"$DEDUPE_ERR")"
+  rc=$?
+  assert_eq "create-item --parent with a sibling closed 1h ago → exit 0" "0" "$rc"
+  assert_eq "create-item --parent with a sibling closed 1h ago prints its id" "github:o/r#7" "$(jq -r '.id' <<<"$OUT")"
+  assert_not_contains "create-item --parent with a sibling closed 1h ago creates no issue" "$(<"$STUB/calls.log")" "issue create"
+
+  OUT="$(GH_STUB_SUBISSUES="$(siblings CLOSED "$two_days_ago" T)" GH_STUB_VERSION=2.94.0 \
+    run_create --title T --parent github:o/r#1 --repo o/r 2>"$DEDUPE_ERR")"
+  rc=$?
+  assert_eq "create-item --parent with a sibling closed 2 days ago → exit 0" "0" "$rc"
+  assert_eq "create-item --parent with a sibling closed 2 days ago creates a new issue" "github:o/r#42" "$(jq -r '.id' <<<"$OUT")"
+  assert_contains "create-item --parent with a sibling closed 2 days ago calls issue create" "$(<"$STUB/calls.log")" "issue create"
+
+  OUT="$(GH_STUB_SUBISSUES="$(siblings OPEN null 'T2')" GH_STUB_VERSION=2.94.0 \
+    run_create --title T --parent github:o/r#1 --repo o/r 2>"$DEDUPE_ERR")"
+  assert_eq "create-item --parent with a differently titled sibling creates a new issue" "github:o/r#42" "$(jq -r '.id' <<<"$OUT")"
+  rm -f "$DEDUPE_ERR"
 
   # CLAUDE_CODE_REMOTE=true: the cloud proxy refuses GraphQL, so gh 2.94 takes REST.
   OUT="$(CLAUDE_CODE_REMOTE=true GH_STUB_VERSION=2.94.0 run_create --title t --labels a --repo o/r)"

plugins/work-items/tools/work-item-tracker/adapters/local-markdown/README.md

@@ -54,6 +54,11 @@ search, and aggregation stay on those verbs; do not invent a query language
 against the markdown files. `--assignee`, `--search`, and `stats` projections
 that need item bodies or update times are **unsupported** on this adapter.
 `create-item` records `created_at`; items created before it read `null`.
+The adapter has no close verb: close an item by editing its file to `state:
+"closed"` and adding `closed_at` (a UTC ISO-8601 string, e.g.
+`"2026-11-03T12:00:00Z"`). Without `closed_at`, `create-item --parent` counts
+the closed child as closed more than 24 hours ago and files a new same-titled
+sibling (CONTRACT.md "local-markdown adapter").
 
 ## Auth
 

plugins/work-items/tools/work-item-tracker/adapters/local-markdown/create-item.sh

@@ -85,6 +85,33 @@ for blocker in "${blocker_ids[@]+"${blocker_ids[@]}"}"; do
   }
 done
 
+# Sibling dedupe (CONTRACT.md "Verbs"): a child of the parent with the same trimmed title,
+# open or closed within 24 hours by its `closed_at`, is returned instead of a new item. A
+# closed child with no `closed_at` counts as closed earlier. An open match wins over a closed one.
+if [[ -n "$parent" ]]; then
+  sibling="" sibling_state=""
+  for n in $(wit_item_numbers); do
+    file="$(wit_item_file "$n")"
+    [[ "$(wit_fm_field "$file" parent)" == "$parent_id" ]] || continue
+    state="$(wit_fm_field "$file" state)"
+    jq -en --arg title "$title" --argjson stored "$(wit_fm_field "$file" title)" \
+      --argjson state "$state" --argjson closed_at "$(wit_fm_field "$file" closed_at | grep . || echo null)" '
+      def trimmed: gsub("^[[:space:]]+|[[:space:]]+$"; "");
+      ($stored | trimmed) == ($title | trimmed)
+      and ($state == "open" or ($state == "closed" and ($closed_at | type) == "string"
+        and (($closed_at | sub("\\.[0-9]+"; "") | fromdateiso8601) > now - 86400)))' >/dev/null 2>&1 || continue
+    sibling="$n" sibling_state="$state"
+    [[ "$state" == '"open"' ]] && break
+  done
+  if [[ -n "$sibling" ]]; then
+    printf 'create-item: %s already has %s child %s titled "%s"; created nothing\n' \
+      "$parent" "$(jq -r . <<<"$sibling_state")" \
+      "$(jq -r . <<<"$(wit_fm_field "$(wit_item_file "$sibling")" id)")" "$title" >&2
+    wit_emit_local_item "$sibling"
+    exit 0
+  fi
+fi
+
 ns="${repo_override:-$WIT_LOCAL_DEFAULT_NS}"
 # owner/repo must match the ID grammar's char class (lib/id.sh); an out-of-grammar
 # --repo would otherwise mint an ID that get-item and later verbs cannot parse.

plugins/work-items/tools/work-item-tracker/adapters/local-markdown/create-item.test.sh

@@ -33,4 +33,54 @@ WIT_STORAGE_DIR="$STORE" bash "$S" --title orphan --blocked-by "local-markdown:l
 assert_eq "a missing --blocked-by is not-found (5), not a dead edge" "5" "$?"
 rm -rf "$STORE"
 
+# Sibling dedupe under --parent: an open child with the same trimmed title, or one
+# closed within 24 hours by its closed_at, is returned; one closed earlier is not.
+close_child() { # <file> <closed_at JSON, or empty for none>
+  awk -v c="$2" '$0 == "state: \"open\"" { print "state: \"closed\""; if (c != "") print "closed_at: " c; next } { print }' \
+    "$1" >"$1.new" && mv "$1.new" "$1"
+}
+STORE="$(mktemp -d "$TMP_ROOT/d.XXXXXX")"
+PARENT="$(WIT_STORAGE_DIR="$STORE" bash "$S" --title parent | jq -r '.id')"
+CHILD="$(WIT_STORAGE_DIR="$STORE" bash "$S" --title "  T " --parent "$PARENT" | jq -r '.id')"
+CHILD_FILE="$STORE/${CHILD##*#}.md"
+ERR="$(mktemp "$TMP_ROOT/f.XXXXXX")"
+
+OUT="$(WIT_STORAGE_DIR="$STORE" bash "$S" --title T --parent "$PARENT" 2>"$ERR")"
+assert_eq "an open sibling titled T → exit 0" "0" "$?"
+assert_eq "an open sibling titled T prints its id" "$CHILD" "$(jq -r '.id' <<<"$OUT")"
+assert_eq "an open sibling titled T creates no item" "2" "$(find "$STORE" -name '*.md' | wc -l | tr -d ' ')"
+assert_contains "an open sibling titled T is named on stderr" "$(<"$ERR")" "$CHILD"
+
+close_child "$CHILD_FILE" "\"$(jq -rn 'now - 3600 | todate')\""
+OUT="$(WIT_STORAGE_DIR="$STORE" bash "$S" --title T --parent "$PARENT" 2>"$ERR")"
+assert_eq "a sibling closed 1h ago → exit 0" "0" "$?"
+assert_eq "a sibling closed 1h ago prints its id" "$CHILD" "$(jq -r '.id' <<<"$OUT")"
+assert_eq "a sibling closed 1h ago creates no item" "2" "$(find "$STORE" -name '*.md' | wc -l | tr -d ' ')"
+
+OUT="$(WIT_STORAGE_DIR="$STORE" bash "$S" --title T 2>"$ERR")"
+assert_eq "without --parent a same-titled item is still created" "false" \
+  "$(jq -r --arg c "$CHILD" '.id == $c' <<<"$OUT")"
+rm -rf "$STORE"
+
+STORE="$(mktemp -d "$TMP_ROOT/d.XXXXXX")"
+PARENT="$(WIT_STORAGE_DIR="$STORE" bash "$S" --title parent | jq -r '.id')"
+CHILD="$(WIT_STORAGE_DIR="$STORE" bash "$S" --title T --parent "$PARENT" | jq -r '.id')"
+close_child "$STORE/${CHILD##*#}.md" "\"$(jq -rn 'now - 172800 | todate')\""
+OUT="$(WIT_STORAGE_DIR="$STORE" bash "$S" --title T --parent "$PARENT" 2>"$ERR")"
+assert_eq "a sibling closed 2 days ago → exit 0" "0" "$?"
+assert_eq "a sibling closed 2 days ago does not block a new create" "false" \
+  "$(jq -r --arg c "$CHILD" '.id == $c' <<<"$OUT")"
+assert_eq "a sibling closed 2 days ago: the new item is a child of the parent" "$PARENT" \
+  "$(jq -r '.parent_id' <<<"$OUT")"
+rm -rf "$STORE"
+
+STORE="$(mktemp -d "$TMP_ROOT/d.XXXXXX")"
+PARENT="$(WIT_STORAGE_DIR="$STORE" bash "$S" --title parent | jq -r '.id')"
+CHILD="$(WIT_STORAGE_DIR="$STORE" bash "$S" --title T --parent "$PARENT" | jq -r '.id')"
+close_child "$STORE/${CHILD##*#}.md" ""
+OUT="$(WIT_STORAGE_DIR="$STORE" bash "$S" --title T --parent "$PARENT" 2>"$ERR")"
+assert_eq "a closed sibling with no closed_at does not block a new create" "false" \
+  "$(jq -r --arg c "$CHILD" '.id == $c' <<<"$OUT")"
+rm -rf "$STORE" "$ERR"
+
 [[ $FAILED -eq 0 ]] || exit 1