Syntax error on template while trying to default variable - ansible

Question

What I'm trying to do
Everything concern HTTP requests.
Create something using POST API, if created I can get the resource id
If resource already created, it returns 422 status code
If 422 status code, get resource by name so I can access it's id
Create another resource with the given id inside its request body
The code I have
- name: Create cluster
uri:
url: '{{ rancher_url }}/v3/cluster'
method: POST
body: {"type":"cluster","nodes":[],"rancherKubernetesEngineConfig":{"ignoreDockerVersion":true, "network":{"type":"networkConfig","plugin":"{{ rancher_network_provider }}"}},"name":"{{ rancher_cluster_name }}"}
status_code: 201, 422
body_format: json
headers:
Authorization: "Bearer {{ api_key_result.json.token }}"
validate_certs: "{{ validate_certs }}"
register: cluster_created
- name: Cluster already exists, retrieving id
uri:
url: '{{ rancher_url }}/v3/cluster?name={{ rancher_cluster_name }}'
method: GET
status_code: 200
headers:
Authorization: "Bearer {{ api_key_result.json.token }}"
body_format: json
validate_certs: "{{ validate_certs }}"
register: cluster_found
when: cluster_created.status == 422
- name: Get command to launch for nodes
uri:
url: '{{ rancher_url }}/v3/clusterregistrationtoken'
method: POST
body: {"type":"clusterRegistrationToken","clusterId":"{{cluster_created.json.id | cluster_found.json.data[0].id}}"}
status_code: 201
body_format: json
headers:
Authorization: "Bearer {{ api_key_result.json.token }}"
validate_certs: "{{ validate_certs }}"
register: node_command_result
So basically I want this line to work : {{cluster_created.json.id | cluster_found.json.data[0].id}}
The error I get
TASK [rancher_worker : Get command to launch for nodes] ***************************************************************************************************************************************************************************************
fatal: [51.15.25.38]: FAILED! => {"msg": "template error while templating string: expected token 'end of print statement', got '['. String: {{cluster_created.json.id | cluster_found.json.data[0].id}}"}
What do you think ?
Thanks for your help :)