> For the complete documentation index, see [llms.txt](https://dev.guardian.hedera.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://dev.guardian.hedera.com/guardian/workspace/policies/library-of-policy-examples/trustchain-reports.md).
# TrustChain reports
For a demo example of following steps, here is the policy timestamp: **1675176247.137536341**
## **Task**
Create a report to check a chain of documents.
## **Preparation**
We will use [example 4](/guardian/workspace/policies/library-of-policy-examples/mrv-document-operations.md) to assemble multiple documents to build a realistic-looking *Trustchain*.
Let’s add several additional attributes into the documents to simplify the document search.
## **Building the trustchain report:**
1. Using the ‘***reportBlock***’
1.1 Add new container
1.2 Add ‘***reportBlock***’
In Guardian policy ‘**reportBlock**’ finds VP documents based on their *id* or *hash* and displays document information, related policy and token information. To retrieve the linked information ‘**reportItemBlock**’ must be used.
1.3 We will build the following chain in this example: **mint \_VP – MRV Report – Project (approved and signed the the Approver) – Approver document – Project (created and signed by the user) – User document.**\_
We will need 6 ‘**reportItemBlock**’ items correspondingly, 1 per each document.
The ‘**reportItemBlock**’ items are executed sequentially, thus in the filter for each consecutive ‘**reportItemBlock**’ we can use values from the previous blocks/documents.
1.3.1 ‘**mint\_document**’. To find this document which described the token mint operation we will use one of the **Common Variables** - *actionId*
1.3.2 ’**report\_document***’*. To find the MRV report (i.e. data document which was the basis of the decision to mint tokens) we will also use one of the **Common Variables** – *documentId*
To find further documents we will need to use values from the **Ref** variable which point to the previous document. Let’s save in a new variable:
1.3.3 ’**project\_document(approver)***’* - Lets use the previously defined variable alongside the static filtration parameters.
Save the author of the document signature so we can display the information about the user later
**Use the same approach to continue the chain until the end.**
1.3.4 ***’*****approver\_document*****’***
1.3.5 ’**project\_document(user)***’*
1.3.6 ’**user\_document***’*
2. To activate the ‘**reportBlock**’ an id or a hash of the VP document is needed, we will add the grid containing the list of the VP documents and links to the trustchain.
2.1 Add ‘**interfaceContainerBlock**’, ‘**interfaceDocumentsSourceBlock**’ and ‘**documentsSourceAddon**’
2.2 Add new column with the type **BUTTON**
Setting the **Action** to LINK will cause the Policy Engine to attempt to switch the display to the target policy block upon the user clicking the link (if possible).
## **Demo**
### VPs:
### Trustchain: