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+# Blockchain API Sessions and Permissions
+
+## Sessions permissions storage
+
+### Get permissions list for account
+
+Used to get account list of active sessions
+
+`GET /v1/sessions/{address}?projectId={projectId}`
+
+* `address` - CAIP-10 address format.
+* `projectId` - Required. The project identifier.
+
+#### Success response body:
+
+```typescript
+{
+    pci: string[] // List of sessions PCIs for this account
+}
+```
+
+#### Response error codes:
+
+* `400 Bad request` - Invalid requested address format.
+
+### Get permissions by address
+
+Used to get permissions by address
+
+`GET /v1/sessions/{address}?projectId={projectId}`
+
+* `address` - CAIP-10 address format.
+* `projectId` - Required. The project identifier.
+
+#### Success response body:
+
+The response is a list of PCIs with permissions and policy:
+
+```typescript
+{
+    "pcis": [pci]
+}
+```
+
+The `pci` object:
+
+```typescript
+{
+    "project":
+    {
+      "id": string,
+      "name": string,
+      "url": ?string,
+      "iconUrl": ?string,
+    }
+    "pci": string,
+    "expiration": number,
+    "createdAt": number,
+    "permissions": [permission]
+    "policies": [policy],
+    "context": string
+}
+```
+
+#### Response error codes:
+
+* `400 Bad request` - Invalid requested address format or PCI not found.
+
+## Add a new permission 
+
+Creating a new permission session for the account
+
+`POST /v1/sessions/{address}?projectId={projectId}`
+
+* `address` - CAIP-10 address format.
+* `projectId` - Required. The project identifier.
+
+### Request body:
+
+The POST request body should be in JSON format and following schema:
+
+```typescript
+{
+    permission:
+        {
+          "permissionType": string,
+          "data": string,
+          "required": boolean,
+          "onChainValidated": boolean
+        }
+}
+```
+
+#### Success response body:
+
+Response will contain a new generated key and PCI of the new permission.
+
+```typescript
+{
+    pci: string, // New unique permission controller identifier.
+    key: string // Public (verifying) secp256k1 key for the generated PCI key in sec1/der format encoded by base64.
+}
+```
+
+#### Response error codes:
+
+* `400 Bad request` - Invalid parameter format in request.
+
+## Updating permissions context
+
+Updating permissions context for the certain permission idenitifier.
+
+`POST /v1/sessions/{address}/context?projectId={projectId}`
+
+* `address` - CAIP-10 address format.
+* `projectId` - Required. The project identifier.
+
+### Request body:
+
+The POST request body should be in JSON format and following schema based on the [ERC-7715](https://github.com/ethereum/ERCs/blob/a75e2d80698441f5da9e0fe98d38122a862aed89/ERCS/erc-7715.md#signers):
+
+```typescript
+{
+    pci: string, // PCI to update
+    signature: string, // Signature of canonicalized JSON `context` object signed by the key provided during the permission creation. The signature must be provided as DER, SEC1 and encoded in Base64 format.
+    context: {
+      signer: {
+        type: string,
+        data:{
+          ids: string[],
+        }
+      },
+      expiry: number,
+      signerData: {
+        userOpBuilder: string
+      },
+      factory: string,
+      factoryData: string,
+      permissionsContext: string
+    }
+}
+```
+
+#### Success response body:
+
+* `200 Ok` - Successfully updated.
+
+#### Response error codes:
+
+* `400 Bad request` - Invalid parameter format in request.
+* `401 Unauthorized` - Invalid signature.
+
+## Revoke permission 
+
+Revoking a permission from account sessions.
+
+`POST /v1/sessions/{address}/revoke?projectId={projectId}`
+
+* `address` - CAIP-10 address format.
+* `projectId` - Required. The project identifier.
+
+### Request body:
+
+The POST request body should be in JSON format and following schema:
+
+```typescript
+{
+    pci: string, // PCI to revoke.
+    signature: string, // Signature of signed `pci` field by the key provided during the permission creation. The signature must be provided as DER, SEC1 and encoded in Base64 format.
+}
+```
+
+#### Success response body:
+
+* `200 Ok` - Successfully revoked.
+
+#### Response error codes:
+
+* `400 Bad request` - Invalid parameter format in request.
+* `401 Unauthorized` - Invalid signature.