diff --git a/apps/authz/src/app/opa/opa.service.ts b/apps/authz/src/app/opa/opa.service.ts
index 8f1285e86..1f987cea2 100644
--- a/apps/authz/src/app/opa/opa.service.ts
+++ b/apps/authz/src/app/opa/opa.service.ts
@@ -2,13 +2,13 @@ import { Injectable, Logger, OnApplicationBootstrap } from '@nestjs/common'
 import { loadPolicy } from '@open-policy-agent/opa-wasm'
 import { readFileSync, writeFileSync } from 'fs'
 import Handlebars from 'handlebars'
-import { isEmpty } from 'lodash'
 import path from 'path'
 import * as R from 'remeda'
 import { v4 as uuidv4 } from 'uuid'
 import { RegoData, User, UserGroup, WalletGroup } from '../../shared/types/entities.types'
-import { Criterion, Policy, Then } from '../../shared/types/policy.type'
+import { Policy } from '../../shared/types/policy.type'
 import { OpaResult, RegoInput } from '../../shared/types/rego'
+import { criterionToString, reasonToString } from '../../shared/utils/opa.utils'
 import { AdminRepository } from '../persistence/repository/admin.repository'
 
 type PromiseType<T extends Promise<unknown>> = T extends Promise<infer U> ? U : never
@@ -41,52 +41,9 @@ export class OpaService implements OnApplicationBootstrap {
   }
 
   generateRegoFile(policies: Policy[]): string {
-    Handlebars.registerHelper('criterion', function (item) {
-      const criterion: Criterion = item.criterion
-      const args = item.args
+    Handlebars.registerHelper('criterion', criterionToString)
 
-      if (args === null) {
-        return `${criterion}`
-      }
-
-      if (!isEmpty(args)) {
-        if (Array.isArray(args)) {
-          if (typeof args[0] === 'string') {
-            return `${criterion}({${args.map((el) => `"${el}"`).join(', ')}})`
-          }
-
-          if (criterion === Criterion.CHECK_APPROVALS) {
-            return `approvals = ${criterion}([${args.map((el) => JSON.stringify(el)).join(', ')}])`
-          }
-
-          return `${criterion}([${args.map((el) => JSON.stringify(el)).join(', ')}])`
-        }
-
-        return `${criterion}(${JSON.stringify(args)})`
-      }
-    })
-
-    Handlebars.registerHelper('reason', function (item) {
-      if (item.then === Then.PERMIT) {
-        const reason = [
-          `"type": "${item.then}"`,
-          `"policyId": "${item.name}"`,
-          '"approvalsSatisfied": approvals.approvalsSatisfied',
-          '"approvalsMissing": approvals.approvalsMissing'
-        ]
-        return `reason = {${reason.join(', ')}}`
-      }
-
-      if (item.then === Then.FORBID) {
-        const reason = {
-          type: item.then,
-          policyId: item.name,
-          approvalsSatisfied: [],
-          approvalsMissing: []
-        }
-        return `reason = ${JSON.stringify(reason)}`
-      }
-    })
+    Handlebars.registerHelper('reason', reasonToString)
 
     const templateSource = readFileSync('./apps/authz/src/opa/template/template.hbs', 'utf-8')
 
diff --git a/apps/authz/src/shared/__test__/unit/opa.utils.spec.ts b/apps/authz/src/shared/__test__/unit/opa.utils.spec.ts
new file mode 100644
index 000000000..f4c929210
--- /dev/null
+++ b/apps/authz/src/shared/__test__/unit/opa.utils.spec.ts
@@ -0,0 +1,93 @@
+import { EntityType, ValueOperators } from '@narval/authz-shared'
+import {
+  ApprovalsCriterion,
+  Criterion,
+  ERC1155TransfersCriterion,
+  IntentAmountCriterion,
+  NonceRequiredCriterion,
+  Policy,
+  Then,
+  WalletAddressCriterion
+} from '../../types/policy.type'
+import { criterionToString, reasonToString } from '../../utils/opa.utils'
+
+describe('criterionToString', () => {
+  it('returns criterion if args are null', () => {
+    const item: NonceRequiredCriterion = {
+      criterion: Criterion.CHECK_NONCE_EXISTS,
+      args: null
+    }
+    expect(criterionToString(item)).toEqual(Criterion.CHECK_NONCE_EXISTS)
+  })
+
+  it('returns criterion if args is an array of strings', () => {
+    const item: WalletAddressCriterion = {
+      criterion: Criterion.CHECK_WALLET_ADDRESS,
+      args: ['0x123', '0x456']
+    }
+    expect(criterionToString(item)).toEqual(`${Criterion.CHECK_WALLET_ADDRESS}({"0x123", "0x456"})`)
+  })
+
+  it('returns criterion if args is an array of objects', () => {
+    const item: ERC1155TransfersCriterion = {
+      criterion: Criterion.CHECK_ERC1155_TRANSFERS,
+      args: [{ tokenId: 'eip155:137/erc1155:0x12345/123', operator: ValueOperators.LESS_THAN_OR_EQUAL, value: '5' }]
+    }
+    expect(criterionToString(item)).toEqual(
+      `${Criterion.CHECK_ERC1155_TRANSFERS}([${item.args.map((el) => JSON.stringify(el)).join(', ')}])`
+    )
+  })
+
+  it('returns criterion if args is an object', () => {
+    const item: IntentAmountCriterion = {
+      criterion: Criterion.CHECK_INTENT_AMOUNT,
+      args: {
+        currency: '*',
+        operator: ValueOperators.LESS_THAN_OR_EQUAL,
+        value: '1000000000000000000'
+      }
+    }
+    expect(criterionToString(item)).toEqual(`${Criterion.CHECK_INTENT_AMOUNT}(${JSON.stringify(item.args)})`)
+  })
+
+  it('returns approvals criterion', () => {
+    const item: ApprovalsCriterion = {
+      criterion: Criterion.CHECK_APPROVALS,
+      args: [
+        {
+          approvalCount: 2,
+          countPrincipal: false,
+          approvalEntityType: EntityType.User,
+          entityIds: ['aa@narval.xyz']
+        }
+      ]
+    }
+    expect(criterionToString(item)).toEqual(
+      `approvals = ${Criterion.CHECK_APPROVALS}([${item.args.map((el) => JSON.stringify(el)).join(', ')}])`
+    )
+  })
+})
+
+describe('reasonToString', () => {
+  it('returns reason for PERMIT rules', () => {
+    const item: Policy = {
+      then: Then.PERMIT,
+      name: 'policyId',
+      when: []
+    }
+    expect(reasonToString(item)).toBe(
+      'reason = {"type":"permit","policyId":"policyId","approvalsSatisfied":approvals.approvalsSatisfied,"approvalsMissing":approvals.approvalsMissing}'
+    )
+  })
+
+  it('returns reason for FORBID rules', () => {
+    const item: Policy = {
+      then: Then.FORBID,
+      name: 'policyId',
+      when: []
+    }
+    expect(reasonToString(item)).toBe(
+      'reason = {"type":"forbid","policyId":"policyId","approvalsSatisfied":[],"approvalsMissing":[]}'
+    )
+  })
+})
diff --git a/apps/authz/src/shared/types/policy.type.ts b/apps/authz/src/shared/types/policy.type.ts
index cc54c56c6..6dda5f06a 100644
--- a/apps/authz/src/shared/types/policy.type.ts
+++ b/apps/authz/src/shared/types/policy.type.ts
@@ -249,7 +249,7 @@ class BaseCriterion {
   criterion: Criterion
 }
 
-class ActionCriterion extends BaseCriterion {
+export class ActionCriterion extends BaseCriterion {
   @ValidateCriterion(Criterion.CHECK_ACTION)
   criterion: typeof Criterion.CHECK_ACTION
 
@@ -257,14 +257,14 @@ class ActionCriterion extends BaseCriterion {
   args: Action[]
 }
 
-class ResourceIntegrityCriterion extends BaseCriterion {
+export class ResourceIntegrityCriterion extends BaseCriterion {
   @ValidateCriterion(Criterion.CHECK_RESOURCE_INTEGRITY)
   criterion: typeof Criterion.CHECK_RESOURCE_INTEGRITY
 
   args: null
 }
 
-class PrincipalIdCriterion extends BaseCriterion {
+export class PrincipalIdCriterion extends BaseCriterion {
   @ValidateCriterion(Criterion.CHECK_PRINCIPAL_ID)
   criterion: typeof Criterion.CHECK_PRINCIPAL_ID
 
@@ -272,7 +272,7 @@ class PrincipalIdCriterion extends BaseCriterion {
   args: string[]
 }
 
-class PrincipalRoleCriterion extends BaseCriterion {
+export class PrincipalRoleCriterion extends BaseCriterion {
   @ValidateCriterion(Criterion.CHECK_PRINCIPAL_ROLE)
   criterion: typeof Criterion.CHECK_PRINCIPAL_ROLE
 
@@ -280,7 +280,7 @@ class PrincipalRoleCriterion extends BaseCriterion {
   args: UserRole[]
 }
 
-class PrincipalGroupCriterion extends BaseCriterion {
+export class PrincipalGroupCriterion extends BaseCriterion {
   @ValidateCriterion(Criterion.CHECK_PRINCIPAL_GROUP)
   criterion: typeof Criterion.CHECK_PRINCIPAL_GROUP
 
@@ -288,7 +288,7 @@ class PrincipalGroupCriterion extends BaseCriterion {
   args: string[]
 }
 
-class WalletIdCriterion extends BaseCriterion {
+export class WalletIdCriterion extends BaseCriterion {
   @ValidateCriterion(Criterion.CHECK_WALLET_ID)
   criterion: typeof Criterion.CHECK_WALLET_ID
 
@@ -296,7 +296,7 @@ class WalletIdCriterion extends BaseCriterion {
   args: string[]
 }
 
-class WalletAddressCriterion extends BaseCriterion {
+export class WalletAddressCriterion extends BaseCriterion {
   @ValidateCriterion(Criterion.CHECK_WALLET_ADDRESS)
   criterion: typeof Criterion.CHECK_WALLET_ADDRESS
 
@@ -304,7 +304,7 @@ class WalletAddressCriterion extends BaseCriterion {
   args: string[]
 }
 
-class WalletAccountTypeCriterion extends BaseCriterion {
+export class WalletAccountTypeCriterion extends BaseCriterion {
   @ValidateCriterion(Criterion.CHECK_WALLET_ACCOUNT_TYPE)
   criterion: typeof Criterion.CHECK_WALLET_ACCOUNT_TYPE
 
@@ -312,7 +312,7 @@ class WalletAccountTypeCriterion extends BaseCriterion {
   args: AccountType[]
 }
 
-class WalletChainIdCriterion extends BaseCriterion {
+export class WalletChainIdCriterion extends BaseCriterion {
   @ValidateCriterion(Criterion.CHECK_WALLET_CHAIN_ID)
   criterion: typeof Criterion.CHECK_WALLET_CHAIN_ID
 
@@ -320,7 +320,7 @@ class WalletChainIdCriterion extends BaseCriterion {
   args: string[]
 }
 
-class WalletGroupCriterion extends BaseCriterion {
+export class WalletGroupCriterion extends BaseCriterion {
   @ValidateCriterion(Criterion.CHECK_WALLET_GROUP)
   criterion: typeof Criterion.CHECK_WALLET_GROUP
 
@@ -328,7 +328,7 @@ class WalletGroupCriterion extends BaseCriterion {
   args: string[]
 }
 
-class IntentTypeCriterion extends BaseCriterion {
+export class IntentTypeCriterion extends BaseCriterion {
   @ValidateCriterion(Criterion.CHECK_INTENT_TYPE)
   criterion: typeof Criterion.CHECK_INTENT_TYPE
 
@@ -336,7 +336,7 @@ class IntentTypeCriterion extends BaseCriterion {
   args: Intents[]
 }
 
-class DestinationIdCriterion extends BaseCriterion {
+export class DestinationIdCriterion extends BaseCriterion {
   @ValidateCriterion(Criterion.CHECK_DESTINATION_ID)
   criterion: typeof Criterion.CHECK_DESTINATION_ID
 
@@ -345,7 +345,7 @@ class DestinationIdCriterion extends BaseCriterion {
   args: AccountId[]
 }
 
-class DestinationAddressCriterion extends BaseCriterion {
+export class DestinationAddressCriterion extends BaseCriterion {
   @ValidateCriterion(Criterion.CHECK_DESTINATION_ADDRESS)
   criterion: typeof Criterion.CHECK_DESTINATION_ADDRESS
 
@@ -353,7 +353,7 @@ class DestinationAddressCriterion extends BaseCriterion {
   args: string[]
 }
 
-class DestinationAccountTypeCriterion extends BaseCriterion {
+export class DestinationAccountTypeCriterion extends BaseCriterion {
   @ValidateCriterion(Criterion.CHECK_DESTINATION_ACCOUNT_TYPE)
   criterion: typeof Criterion.CHECK_DESTINATION_ACCOUNT_TYPE
 
@@ -361,7 +361,7 @@ class DestinationAccountTypeCriterion extends BaseCriterion {
   args: AccountType[]
 }
 
-class DestinationClassificationCriterion extends BaseCriterion {
+export class DestinationClassificationCriterion extends BaseCriterion {
   @ValidateCriterion(Criterion.CHECK_DESTINATION_CLASSIFICATION)
   criterion: typeof Criterion.CHECK_DESTINATION_CLASSIFICATION
 
@@ -369,7 +369,7 @@ class DestinationClassificationCriterion extends BaseCriterion {
   args: string[]
 }
 
-class IntentContractCriterion extends BaseCriterion {
+export class IntentContractCriterion extends BaseCriterion {
   @ValidateCriterion(Criterion.CHECK_INTENT_CONTRACT)
   criterion: typeof Criterion.CHECK_INTENT_CONTRACT
 
@@ -378,7 +378,7 @@ class IntentContractCriterion extends BaseCriterion {
   args: AccountId[]
 }
 
-class IntentTokenCriterion extends BaseCriterion {
+export class IntentTokenCriterion extends BaseCriterion {
   @ValidateCriterion(Criterion.CHECK_INTENT_TOKEN)
   criterion: typeof Criterion.CHECK_INTENT_TOKEN
 
@@ -387,7 +387,7 @@ class IntentTokenCriterion extends BaseCriterion {
   args: AssetId[]
 }
 
-class IntentSpenderCriterion extends BaseCriterion {
+export class IntentSpenderCriterion extends BaseCriterion {
   @ValidateCriterion(Criterion.CHECK_INTENT_SPENDER)
   criterion: typeof Criterion.CHECK_INTENT_SPENDER
 
@@ -396,7 +396,7 @@ class IntentSpenderCriterion extends BaseCriterion {
   args: AccountId[]
 }
 
-class IntentChainIdCriterion extends BaseCriterion {
+export class IntentChainIdCriterion extends BaseCriterion {
   @ValidateCriterion(Criterion.CHECK_INTENT_CHAIN_ID)
   criterion: typeof Criterion.CHECK_INTENT_CHAIN_ID
 
@@ -404,7 +404,7 @@ class IntentChainIdCriterion extends BaseCriterion {
   args: string[]
 }
 
-class IntentHexSignatureCriterion extends BaseCriterion {
+export class IntentHexSignatureCriterion extends BaseCriterion {
   @ValidateCriterion(Criterion.CHECK_INTENT_HEX_SIGNATURE)
   criterion: typeof Criterion.CHECK_INTENT_HEX_SIGNATURE
 
@@ -413,7 +413,7 @@ class IntentHexSignatureCriterion extends BaseCriterion {
   args: Hex[]
 }
 
-class IntentAmountCriterion extends BaseCriterion {
+export class IntentAmountCriterion extends BaseCriterion {
   @ValidateCriterion(Criterion.CHECK_INTENT_AMOUNT)
   criterion: typeof Criterion.CHECK_INTENT_AMOUNT
 
@@ -422,7 +422,7 @@ class IntentAmountCriterion extends BaseCriterion {
   args: AmountCondition
 }
 
-class ERC721TokenIdCriterion extends BaseCriterion {
+export class ERC721TokenIdCriterion extends BaseCriterion {
   @ValidateCriterion(Criterion.CHECK_ERC721_TOKEN_ID)
   criterion: typeof Criterion.CHECK_ERC721_TOKEN_ID
 
@@ -431,7 +431,7 @@ class ERC721TokenIdCriterion extends BaseCriterion {
   args: AssetId[]
 }
 
-class ERC1155TokenIdCriterion extends BaseCriterion {
+export class ERC1155TokenIdCriterion extends BaseCriterion {
   @ValidateCriterion(Criterion.CHECK_ERC1155_TOKEN_ID)
   criterion: typeof Criterion.CHECK_ERC1155_TOKEN_ID
 
@@ -440,7 +440,7 @@ class ERC1155TokenIdCriterion extends BaseCriterion {
   args: AssetId[]
 }
 
-class ERC1155TransfersCriterion extends BaseCriterion {
+export class ERC1155TransfersCriterion extends BaseCriterion {
   @ValidateCriterion(Criterion.CHECK_ERC1155_TRANSFERS)
   criterion: typeof Criterion.CHECK_ERC1155_TRANSFERS
 
@@ -449,7 +449,7 @@ class ERC1155TransfersCriterion extends BaseCriterion {
   args: ERC1155AmountCondition[]
 }
 
-class IntentMessageCriterion extends BaseCriterion {
+export class IntentMessageCriterion extends BaseCriterion {
   @ValidateCriterion(Criterion.CHECK_INTENT_MESSAGE)
   criterion: typeof Criterion.CHECK_INTENT_MESSAGE
 
@@ -458,7 +458,7 @@ class IntentMessageCriterion extends BaseCriterion {
   args: SignMessageCondition
 }
 
-class IntentPayloadCriterion extends BaseCriterion {
+export class IntentPayloadCriterion extends BaseCriterion {
   @ValidateCriterion(Criterion.CHECK_INTENT_PAYLOAD)
   criterion: typeof Criterion.CHECK_INTENT_PAYLOAD
 
@@ -466,7 +466,7 @@ class IntentPayloadCriterion extends BaseCriterion {
   args: string[]
 }
 
-class IntentAlgorithmCriterion extends BaseCriterion {
+export class IntentAlgorithmCriterion extends BaseCriterion {
   @ValidateCriterion(Criterion.CHECK_INTENT_ALGORITHM)
   criterion: typeof Criterion.CHECK_INTENT_ALGORITHM
 
@@ -474,7 +474,7 @@ class IntentAlgorithmCriterion extends BaseCriterion {
   args: Alg[]
 }
 
-class IntentDomainCriterion extends BaseCriterion {
+export class IntentDomainCriterion extends BaseCriterion {
   @ValidateCriterion(Criterion.CHECK_INTENT_DOMAIN)
   criterion: typeof Criterion.CHECK_INTENT_DOMAIN
 
@@ -483,7 +483,7 @@ class IntentDomainCriterion extends BaseCriterion {
   args: SignTypedDataDomainCondition
 }
 
-class PermitDeadlineCriterion extends BaseCriterion {
+export class PermitDeadlineCriterion extends BaseCriterion {
   @ValidateCriterion(Criterion.CHECK_PERMIT_DEADLINE)
   criterion: typeof Criterion.CHECK_PERMIT_DEADLINE
 
@@ -492,7 +492,7 @@ class PermitDeadlineCriterion extends BaseCriterion {
   args: PermitDeadlineCondition
 }
 
-class GasFeeAmountCriterion extends BaseCriterion {
+export class GasFeeAmountCriterion extends BaseCriterion {
   @ValidateCriterion(Criterion.CHECK_GAS_FEE_AMOUNT)
   criterion: typeof Criterion.CHECK_GAS_FEE_AMOUNT
 
@@ -501,21 +501,21 @@ class GasFeeAmountCriterion extends BaseCriterion {
   args: AmountCondition
 }
 
-class NonceRequiredCriterion extends BaseCriterion {
+export class NonceRequiredCriterion extends BaseCriterion {
   @ValidateCriterion(Criterion.CHECK_NONCE_EXISTS)
   criterion: typeof Criterion.CHECK_NONCE_EXISTS
 
   args: null
 }
 
-class NonceNotRequiredCriterion extends BaseCriterion {
+export class NonceNotRequiredCriterion extends BaseCriterion {
   @ValidateCriterion(Criterion.CHECK_NONCE_NOT_EXISTS)
   criterion: typeof Criterion.CHECK_NONCE_NOT_EXISTS
 
   args: null
 }
 
-class ApprovalsCriterion extends BaseCriterion {
+export class ApprovalsCriterion extends BaseCriterion {
   @ValidateCriterion(Criterion.CHECK_APPROVALS)
   criterion: typeof Criterion.CHECK_APPROVALS
 
@@ -524,7 +524,7 @@ class ApprovalsCriterion extends BaseCriterion {
   args: ApprovalCondition[]
 }
 
-class SpendingLimitCriterion extends BaseCriterion {
+export class SpendingLimitCriterion extends BaseCriterion {
   @ValidateCriterion(Criterion.CHECK_SPENDING_LIMIT)
   criterion: typeof Criterion.CHECK_SPENDING_LIMIT
 
@@ -533,6 +533,15 @@ class SpendingLimitCriterion extends BaseCriterion {
   args: SpendingLimitCondition
 }
 
+export type SetPolicyRulesAction = BaseAction & {
+  action: typeof Action.SET_POLICY_RULES
+  data: Policy[]
+}
+
+export type SetPolicyRulesRequest = BaseAdminRequest & {
+  request: SetPolicyRulesAction
+}
+
 const SUPPORTED_CRITERION = [
   ActionCriterion,
   ResourceIntegrityCriterion,
@@ -707,12 +716,3 @@ const instantiateCriterion = (criterion: PolicyCriterion) => {
       throw new Error('Unknown criterion: ' + criterion)
   }
 }
-
-export type SetPolicyRulesAction = BaseAction & {
-  action: typeof Action.SET_POLICY_RULES
-  data: Policy[]
-}
-
-export type SetPolicyRulesRequest = BaseAdminRequest & {
-  request: SetPolicyRulesAction
-}
diff --git a/apps/authz/src/shared/utils/opa.utils.ts b/apps/authz/src/shared/utils/opa.utils.ts
new file mode 100644
index 000000000..9de10d320
--- /dev/null
+++ b/apps/authz/src/shared/utils/opa.utils.ts
@@ -0,0 +1,45 @@
+import { isEmpty } from 'lodash'
+import { Criterion, Policy, PolicyCriterion, Then } from '../types/policy.type'
+
+export const criterionToString = (item: PolicyCriterion) => {
+  const criterion: Criterion = item.criterion
+  const args = item.args
+
+  if (!isEmpty(args)) {
+    if (Array.isArray(args)) {
+      if (typeof args[0] === 'string') {
+        return `${criterion}({${args.map((el) => `"${el}"`).join(', ')}})`
+      }
+
+      if (criterion === Criterion.CHECK_APPROVALS) {
+        return `approvals = ${criterion}([${args.map((el) => JSON.stringify(el)).join(', ')}])`
+      }
+
+      return `${criterion}([${args.map((el) => JSON.stringify(el)).join(', ')}])`
+    }
+
+    return `${criterion}(${JSON.stringify(args)})`
+  }
+
+  return `${criterion}`
+}
+
+export const reasonToString = (item: Policy) => {
+  if (item.then === Then.PERMIT) {
+    const reason = [
+      `"type":"${item.then}"`,
+      `"policyId":"${item.name}"`,
+      '"approvalsSatisfied":approvals.approvalsSatisfied',
+      '"approvalsMissing":approvals.approvalsMissing'
+    ]
+    return `reason = {${reason.join(',')}}`
+  }
+
+  const reason = {
+    type: item.then,
+    policyId: item.name,
+    approvalsSatisfied: [],
+    approvalsMissing: []
+  }
+  return `reason = ${JSON.stringify(reason)}`
+}