feat(examples): support fallback to standard triage summary if custom instructions are omitted

Author: cocosheng-g

examples/workflows/issue-cleanup/README.md

@@ -8,7 +8,7 @@ The Issue Cleanup workflow is designed to automate the triage of stale issues by
 
 1. **Check Code Validity**: Determines if an issue is still relevant against the current codebase. If the issue has already been resolved implicitly, it will close the issue with an explanation.
 2. **Find Duplicates**: Checks if the issue has a more recent duplicate. If a duplicate exists, it closes the issue and links to the duplicate.
-3. **Summarize for Triage**: If an issue is still valid and unique, it provides a summary comment based on customizable instructions (e.g., categorizing it as `Maintainer-only` or `Help-wanted`).
+3. **Summarize for Triage**: If an issue is still valid and unique, it provides a summary comment based on customizable instructions (e.g., categorizing it as `Maintainer-only` or `Help-wanted`). If no custom instructions are provided, it falls back to a standard triage summary (identifying the core problem, impact, and next steps).
 
 ## Usage
 

examples/workflows/issue-cleanup/gemini-issue-cleanup.toml

@@ -31,10 +31,10 @@ You MUST use your tools (like `grep_search`, `read_file`, and `run_shell_command
 
 ### Step 3: Provide Triage Summary
 - If the issue is still valid and NOT a duplicate, add a brief summary comment for further triaging.
-- To formulate your summary, follow these custom instructions:
+- If custom instructions are provided below, use them to formulate your summary. Otherwise, formulate a standard triage summary (e.g., identifying the core problem, potential impact, and recommended next steps for a maintainer).
 ```
 !{echo $CUSTOM_INSTRUCTIONS}
 ```
-- Use `gh issue comment !{echo $ISSUE_NUMBER} --body "### Triage Summary\n\n<your summary based on custom instructions>" --repo !{echo $REPOSITORY}`
+- Use `gh issue comment !{echo $ISSUE_NUMBER} --body "### Triage Summary\n\n<your summary>" --repo !{echo $REPOSITORY}`
 - STOP execution. You are done with this issue.
 """