diff --git a/templates/commands/taskstoissues.md b/templates/commands/taskstoissues.md
index b24e84ee14..459c559302 100644
--- a/templates/commands/taskstoissues.md
+++ b/templates/commands/taskstoissues.md
@@ -1,6 +1,6 @@
 ---
 description: Convert existing tasks into actionable, dependency-ordered GitHub issues for the feature based on available design artifacts.
-tools: ['github/github-mcp-server/issue_write']
+tools: ['github/github-mcp-server/list_issues', 'github/github-mcp-server/issue_write']
 scripts:
   sh: scripts/bash/check-prerequisites.sh --json --require-tasks --include-tasks
   ps: scripts/powershell/check-prerequisites.ps1 -Json -RequireTasks -IncludeTasks
@@ -62,7 +62,10 @@ git config --get remote.origin.url
 > [!CAUTION]
 > ONLY PROCEED TO NEXT STEPS IF THE REMOTE IS A GITHUB URL
 
-1. For each task in the list, use the GitHub MCP server to create a new issue in the repository that is representative of the Git remote.
+1. **Fetch existing issues for deduplication**: Before creating anything, use the GitHub MCP server's `list_issues` tool to list the repository's issues. Do not pass a `state` value, since omitting it makes the tool return both open and closed issues. Request `perPage: 100` to keep the number of calls down, and since the tool uses cursor-based pagination, keep requesting pages with the `after` parameter (using the `endCursor` from the previous response) until all issues have been fetched. Build a set of task IDs that already have an issue by matching each issue title against the task ID pattern `\bT\d{3}\b` (a `T` followed by three digits, on word boundaries so tokens like `ST001` or `T0010` are not matched by mistake). Using a boundary-aware match means titles written as `T001 ...`, `T001: ...` or `[T001] ...` are all recognised. This prevents duplicate issues when the command is re-run after `tasks.md` is regenerated or the skill is re-invoked.
+1. For each task in the list, use the GitHub MCP server to create a new issue in the repository that is representative of the Git remote. Task lines in `tasks.md` start with a markdown checkbox, so first strip the leading `- [ ]` (and any `[P]` / `[US#]` markers) to recover the task ID and its description. Create the issue with a single canonical title of the form `T001: <description>`, with the ID written once followed by the task description (for example, the line `- [ ] T001 Create project structure` becomes the title `T001: Create project structure`).
+   - **Skip** any task whose ID is already present in the set of existing issues from the previous step, and report it (for example, `T001 already has an issue, skipping`).
+   - Only create issues for tasks that do not yet have a matching issue.
 
 > [!CAUTION]
 > UNDER NO CIRCUMSTANCES EVER CREATE ISSUES IN REPOSITORIES THAT DO NOT MATCH THE REMOTE URL