Add GitHub repo link and GitHub MCP usage to links template and agent instructions

Co-authored-by: bearguo <20483603+bearguo@users.noreply.github.com>

Author: Copilot

.github/copilot-instructions.md

@@ -24,7 +24,7 @@ Before creating any files, ask the user for any missing information:
 - **Tech stack**: programming language, frameworks, databases, message queues
 - **Author / owner**: name to put in the document header
 - **Timeline**: start date, end date, key milestones (required only if creating `schedule.md`)
-- **External links**: Figma URL, Feishu doc URL, Slack channel, Jira epic (required only if creating `links.md`)
+- **External links**: Figma URL, Feishu doc URL, Slack channel, Jira epic, GitHub repository URL (required only if creating `links.md`)
 
 Do NOT create any files until you have at minimum: module name and feature description.
 
@@ -43,7 +43,7 @@ For each file to create, copy the corresponding template and fill in the content
 
 | File to create | Template to use | When to create |
 |----------------|-----------------|----------------|
-| `docs/<module-name>/links.md` | `templates/links-template.md` | When user provides external links (Figma, Feishu, Slack, Jira) |
+| `docs/<module-name>/links.md` | `templates/links-template.md` | When user provides external links (Figma, Feishu, Slack, Jira, GitHub) |
 | `docs/<module-name>/tech-design.md` | `templates/tech-design-template.md` | Always — this is required for every module |
 | `docs/<module-name>/tech-design-part2.md` | `templates/tech-design-template.md` (sections only) | When `tech-design.md` exceeds ~500 lines; split overflow sections here |
 | `docs/<module-name>/schedule.md` | `templates/schedule-template.md` | When user provides timeline or asks for a schedule |
@@ -52,10 +52,11 @@ For each file to create, copy the corresponding template and fill in the content
 ### Step 4: Fill In Each File
 
 #### links.md
-- Fill in the four rows: Figma, Feishu Doc, Slack channel, Jira epic
+- Fill in the five rows: Figma, Feishu Doc, Slack channel, Jira epic, GitHub repository
 - Use the exact URLs and channel names provided by the user
-- If the user did not provide a link for one of the four tools, leave it as `#` (placeholder)
+- If the user did not provide a link for one of the five tools, leave it as `#` (placeholder)
 - Do not add rows for tools not in the template (no GitHub Issues, Linear, Confluence, Notion, etc.)
+- **GitHub MCP**: when the user provides a GitHub repository URL, use the GitHub MCP tools to read the repository content (file structure, key source files, existing README, API definitions) and incorporate the findings into `tech-design.md` — use it to understand the current codebase before writing the design
 
 #### tech-design.md
 - Fill in ALL sections from the template; mark sections as "N/A" if not applicable — do not remove them

docs/sample/links.md

@@ -8,3 +8,4 @@
 | 飞书文档 / Feishu Doc | [用户认证需求文档](https://example.feishu.cn/docs/example) | 产品需求文档 (PRD) |
 | Slack       | `#auth-system` | 主要讨论频道 |
 | Jira        | [AUTH-100 Epic](https://jira.example.com/browse/AUTH-100) | 用户认证系统改造 Epic |
+| GitHub      | [org/auth-service](https://github.com/org/auth-service) | 代码仓库（可通过 GitHub MCP 读取内容用于技术设计） |

templates/links-template.md

@@ -10,3 +10,4 @@
 | 飞书文档 / Feishu Doc | [打开飞书文档](#) | 需求文档 / PRD |
 | Slack       | `#channel-name` | 主要讨论频道 |
 | Jira        | [Epic / Story](#) | 需求追踪 |
+| GitHub      | [仓库链接](#) | 代码仓库（可通过 GitHub MCP 读取内容用于技术设计） |