Break a large work item into context-completable GitHub sub-issues, define a 10-20 node architecture and workflow mapping, propose a milestone, and create the issues with gh. Use ONLY when the user explicitly types /github-dev:decompose-issue or asks to decompose or break down work into issues. Do NOT auto-fire from incidental mentions of issues or planning — this creates GitHub issues, a milestone, and a project-tracking state file. Detects TDD applicability, captures dependencies, and writes .claude/state/project-tracking-{slug}.json for the milestone and diagram pipeline.
インストール
Codex または Claude でインストール この Prompt をコピーして Codex、Claude、または他のアシスタントに貼り付けると、Skill ページを確認してインストールできます。
Break a large work item into context-completable GitHub sub-issues, define a 10-20 node architecture and workflow mapping, propose a milestone, and create the issues with gh. Use ONLY when the user explicitly types /github-dev:decompose-issue or asks to decompose or break down work into issues. Do NOT auto-fire from incidental mentions of issues or planning — this creates GitHub issues, a milestone, and a project-tracking state file. Detects TDD applicability, captures dependencies, and writes .claude/state/project-tracking-{slug}.json for the milestone and diagram pipeline.
allowed-tools
Read Write Edit Bash Glob Grep AskUserQuestion
Decompose Work
Hermes Agent Compatibility
When this skill is loaded through Hermes as github-dev:<skill>, map Claude/Codex tool names to Hermes tools:
Claude/Codex term
Hermes tool
Bash
terminal
Read
read_file
Write
write_file
Edit
patch
Glob/Grep
search_files
AskUserQuestion
clarify
Task
delegate_task
Monitor
process
Treat $ARGUMENTS as the natural-language arguments supplied when the user asks Hermes to load the skill. Plugin-provided skills are explicit opt-in loads in Hermes; use skill_view("github-dev:<skill>") (or ask Hermes to load that qualified skill) rather than relying on bare text like github-dev:<skill> ....
Break down large work items into manageable, independent issues. Follow project guidelines in @CLAUDE.md.
Workflow
Check issue numbers: Run gh issue list to view current issue numbers
Discover available components:
Scan .claude/agents/ for custom agents (read YAML frontmatter)
Detect test frameworks (jest.config., pytest.ini, vitest.config., pyproject.toml, etc.)
Check TDD applicability (if user hasn't specified):
Analyze work type: code implementation vs docs/infra/config
If test framework detected + code work → Ask: "Create issues with TDD approach?"
If no test framework → Inform: "TDD not required. (Reason: No test framework detected)"
If non-code work (docs/infra) → Inform: "TDD not required. (Reason: Non-code work)"
If TDD selected: Add <!-- TDD: enabled --> marker to each issue body
Analyze work: Understand core requirements and objectives
Decompose work: Split major tasks into context-completable units - each issue should be completable in a single Claude session without context switching. Group related features together rather than splitting by individual functions
Analyze dependencies: Identify prerequisite tasks
Suggest milestone name: Propose a milestone to group decomposed tasks
Check related PRs (optional): Run gh pr list --state closed --limit 20 for similar work references (skip if none)
Output decomposed issues: Display issues with proposed milestone name
Analyze the codebase and design a 10-20 node flowchart of the project's core workflow. Store as Mermaid in the state file, but present to the user as an ASCII diagram.
Interview: Project Workflow -- Use AskUserQuestion:
"프로젝트의 전체 워크플로우를 다이어그램으로 정리했습니다. 수정할 부분이 있나요?"
Present the proposed workflow as an ASCII diagram (terminal cannot render Mermaid)
The diagram should capture the main data/control flow (not just layers)
Use descriptive node names for easy mapping
User can add/remove/rename nodes and connections
Target: 10-20 nodes with branches and subgroups where logical
Example workflow (ASCII, shown to user in terminal):
Ask about GitHub creation: Use AskUserQuestion to let user decide on milestone and issue creation
Create milestone with Markdown Table in description.
CRITICAL — DO NOT include Mermaid in milestone description. GitHub milestone pages do not render Mermaid; the raw code shows as plain text. Mermaid belongs in issue bodies (Type M-2; see update-progress.md "Type M-2"), never in the milestone description.
Build $MILESTONE_TABLE with the required table block below (canonical spec at update-progress.md:160).
You may prepend objective/scope and dependency-order summary sections required by this file's milestone guidelines.
Inject the TDD marker (if TDD was enabled in Step 3): when creating each issue, prepend <!-- TDD: enabled --> as the first line of the issue body (before **Purpose**:). This is the exact marker resolve-issue Step 1 detects to switch on the TDD workflow. If TDD was not selected in Step 3, omit the prepend entirely — do not write the marker.
Assign issues with --milestone option
After issue creation, update the state file issues map with actual GitHub issue numbers
Add issues to GitHub Project (optional)
Check for existing projects: gh project list --owner <owner> --format json
If no project exists: Display "No project found. You can create one with /gh:init-project" and skip
If project exists: Ask user via AskUserQuestion whether to add issues
If yes: Run gh project item-add <project-number> --owner <owner> --url <issue-url> for each issue
Issue Sizing Principle
Context-Completable Units
Each issue should be designed to be completable in a single Claude session:
Group related features rather than splitting by individual functions
Minimize context switching - all necessary information should be within the issue
Include implementation details - specific enough that no external lookup is needed during execution
Sizing Guidelines
Good (Context-Completable)
Bad (Over-Fragmented)
"Add user authentication with login/logout/session"