Check the real risk of a ServiceNow change before CAB

**Objective:** Independently assess the risk of change `{change-number}` and say whether the recorded risk is right.

**Step 1: Read the change**

Call `servicenow-get-change-request` with number `{change-number}`. Note type, risk, state, planned window, configuration-item and assignment-group.

**Step 2: Blast radius**

* Call `servicenow-get-ci-affected` with task `{change-number}` for the affected CIs.
* Call `servicenow-get-impacted-ci` with task `{change-number}` for the impacted services.
* For each affected CI call `servicenow-get-configuration-item` with name set to it and note environment and operational-status.

**Step 3: Current health of those CIs**

For each affected CI call `servicenow-get-alert` with configuration-item set to its name and state Open. Changing something that is already alarming raises the risk.

**Step 4: Collisions and history**

For each affected CI call `servicenow-get-ci-affected` with configuration-item set to its name. For each other CHG task number found, read it with `servicenow-get-change-request`:

* overlapping planned windows are a collision
* a change on the same CI in the last 30 days that is still open, or closed unsuccessfully, is a warning

**Step 5: Readiness**

Call `servicenow-get-change-task` with change-request `{change-number}` and `servicenow-get-approval` with approval-for `{change-number}`. A change with no Testing task, or with pending approvals close to its start, carries extra risk.

**Step 6: Report**

* Recorded risk vs assessed risk (High, Moderate or Low), with a one-line verdict.
* Evidence table: factor, finding, effect on risk.
* Recommendations: at most three, for example add a test task, move the window, or re-rate the risk.

**Rules & Guidelines:**

* Read-only. Do not call `servicenow-update-change-request`, `servicenow-update-approval`, `servicenow-add-change-task` or any other add- or update- tool.
* Production CIs and impacted business services weigh more than development ones. Say which evidence drove the rating.

**Validation:**

* If `{change-number}` is not found, stop. If it has no affected CIs, rate only on what is known and say the CI list is missing.