Destructive Command Guard · 三段真实拦截证据看板

CClaude Code agent hook · Bash PreToolUse core.git

Agent 试图执行

$ git reset --hard HEAD~5

dcg 面板 · stderr verbatim (EXPLANATION + Safer alternatives 直接印在面板里)

+----------------------------------------------------------------------------+
| !  BLOCKED: Destructive Command Detected                                   |
+----------------------------------------------------------------------------+
|  git reset --hard HEAD~5                                                   |
|  ^^^^^^^^^^^^^^^^                                                          |
|                                                                            |
|  EXPLANATION:                                                              |
|  git reset --hard discards ALL uncommitted changes in your working         |
|  directory AND staging area. This is one of the most dangerous git         |
|  commands because changes that were never committed cannot be recovered    |
|  by any means.                                                             |
|                                                                            |
|  Safer alternatives:                                                       |
|  - git reset --soft <ref>: Move HEAD but keep all changes staged           |
|  - git reset --mixed <ref>: Move HEAD, unstage changes, keep working dir   |
|  - git stash: Save changes before resetting                                |
|                                                                            |
|  Pattern: reset-hard                                                       |
|  Pack: core.git (severity: CRITICAL)                                    |
+----------------------------------------------------------------------------+

rule · core.git:reset-hard severity · CRITICAL decision · deny

Agent → 改用 git stash push -m "wip" 存下未提交改动，再 git reset --soft HEAD~5 只挪 HEAD、保留 staging；跑之前先 git status && git diff 确认不会丢东西。

XCodex CLI agent hook · Bash PreToolUse core.filesystem

Agent 试图执行

$ rm -rf ./src

dcg 面板 · stderr verbatim (此规则不打 EXPLANATION，只印 Pattern / Pack / Regex — 与其他富规则不同)

+----------------------------------------------------------------------------+
| !  BLOCKED: Destructive Command Detected                                   |
+----------------------------------------------------------------------------+
|  rm -rf ./src                                                              |
|     ^^^                                                                    |
|                                                                            |
|                                                                            |
|  Pattern: rm-rf-general                                                    |
|  Pack: core.filesystem (severity: HIGH)                                |
|  Regex: rm\s+-[a-zA-Z]*[rR][a-zA-Z]*f|rm\s+-[a-zA-Z]*f[a-zA-Z]*[rR]        |
+----------------------------------------------------------------------------+

Learn more:
  $ dcg explain "rm -rf ./src"
  $ dcg allowlist add core.filesystem:rm-rf-general --project

hook JSON · agent 真读到的 (stdout permissionDecisionReason, 与 stderr 无关，一定有 Reason)

Reason:      rm -rf is destructive and requires human approval.
             Explain what you want to delete and why, then ask the
             user to run the command manually.

Explanation: Matched destructive pattern core.filesystem:rm-rf-general.
             No additional explanation is available yet. See pack
             documentation for details.

Rule:        core.filesystem:rm-rf-general
Command:     rm -rf ./src

dcg explain · 独立命令 (Suggestions 段, 比 stderr 面板更完整)

Suggestions
• Preview first: List contents first with `ls -la` to verify target
• Safer alternative: Use `rm -ri` for interactive confirmation of each file
    $ rm -ri path/
• Workflow fix: Move to trash instead: `mv path ~/.local/share/Trash/`

rule · core.filesystem:rm-rf-general severity · HIGH decision · deny

Agent → 先说清楚要删什么（./src 是本仓库的应用源码目录、有 12 个已跟踪文件、无未提交改动），改用 rm -ri ./src 逐个确认；或 mv ./src ~/.local/share/Trash/ 走回收站；仍然想清空就请用户手动跑一次 rm -rf。

RCursor agent hook · Bash PreToolUse database.postgresql · opt-in

Agent 试图执行

$ psql -c "DROP TABLE users;"

dcg 面板 · stderr verbatim (EXPLANATION + Safer alternatives 直接印在面板里)

+----------------------------------------------------------------------------+
| !  BLOCKED: Destructive Command Detected                                   |
+----------------------------------------------------------------------------+
|  psql -c "DROP TABLE users;"                                               |
|           ^^^^^^^^^^                                                       |
|                                                                            |
|  EXPLANATION:                                                              |
|  DROP TABLE removes the table structure and ALL data:                      |
|                                                                            |
|  - All rows are deleted                                                    |
|  - Indexes, constraints, triggers are removed                              |
|  - Foreign keys referencing this table may fail                            |
|  - CASCADE drops dependent objects too                                     |
|                                                                            |
|  IF EXISTS only prevents errors - it still drops the table!                |
|                                                                            |
|  Backup table first:                                                       |
|    pg_dump -t tablename dbname > table_backup.sql                          |
|                                                                            |
|  Pattern: drop-table                                                       |
|  Pack: database.postgresql (severity: HIGH)                            |
+----------------------------------------------------------------------------+

rule · database.postgresql:drop-table severity · HIGH decision · deny

Agent → 先备份：pg_dump -t users mydb > users_backup.sql；把行数与外键报回给用户（SELECT COUNT(*) FROM users），得到明确同意后由用户手动跑 DROP，或改用 TRUNCATE users RESTART IDENTITY + 保留 schema 的方案。