diff --git a/plugins/catalog-backend/src/permissions/rules/util.ts b/plugins/catalog-backend/src/permissions/rules/util.ts
index 37544a14f8..ea25e115d2 100644
--- a/plugins/catalog-backend/src/permissions/rules/util.ts
+++ b/plugins/catalog-backend/src/permissions/rules/util.ts
@@ -16,6 +16,7 @@
 
 import { Entity } from '@backstage/catalog-model';
 import { RESOURCE_TYPE_CATALOG_ENTITY } from '@backstage/plugin-catalog-common';
+import { PermissionRuleParams } from '@backstage/plugin-permission-common';
 import {
   makeCreatePermissionRule,
   PermissionRule,
@@ -30,7 +31,7 @@ import { EntitiesSearchFilter } from '../../catalog/types';
  * @alpha
  */
 export type CatalogPermissionRule<
-  TParams extends Record<string, unknown> = Record<string, unknown>,
+  TParams extends PermissionRuleParams = PermissionRuleParams,
 > = PermissionRule<Entity, EntitiesSearchFilter, 'catalog-entity', TParams>;
 
 /**
diff --git a/plugins/permission-common/package.json b/plugins/permission-common/package.json
index fcf1c47ea6..4c31ecc673 100644
--- a/plugins/permission-common/package.json
+++ b/plugins/permission-common/package.json
@@ -43,6 +43,7 @@
   "dependencies": {
     "@backstage/config": "workspace:^",
     "@backstage/errors": "workspace:^",
+    "@backstage/types": "workspace:^",
     "cross-fetch": "^3.1.5",
     "uuid": "^8.0.0",
     "zod": "^3.11.6"
diff --git a/plugins/permission-common/src/PermissionClient.ts b/plugins/permission-common/src/PermissionClient.ts
index 7b429dc46f..c5f56be159 100644
--- a/plugins/permission-common/src/PermissionClient.ts
+++ b/plugins/permission-common/src/PermissionClient.ts
@@ -41,7 +41,7 @@ const permissionCriteriaSchema: z.ZodSchema<
     .object({
       rule: z.string(),
       resourceType: z.string(),
-      params: z.record(z.unknown()),
+      params: z.record(z.any()),
     })
     .or(z.object({ anyOf: z.array(permissionCriteriaSchema).nonempty() }))
     .or(z.object({ allOf: z.array(permissionCriteriaSchema).nonempty() }))
diff --git a/plugins/permission-common/src/types/api.ts b/plugins/permission-common/src/types/api.ts
index 70b9e902b8..ca915a65da 100644
--- a/plugins/permission-common/src/types/api.ts
+++ b/plugins/permission-common/src/types/api.ts
@@ -14,6 +14,7 @@
  * limitations under the License.
  */
 
+import { JsonPrimitive } from '@backstage/types';
 import { ResourcePermission } from '.';
 import { Permission } from './permission';
 
@@ -101,7 +102,7 @@ export type PolicyDecision =
  */
 export type PermissionCondition<
   TResourceType extends string = string,
-  TParams extends Record<string, unknown> = Record<string, unknown>,
+  TParams extends PermissionRuleParams = PermissionRuleParams,
 > = {
   resourceType: TResourceType;
   rule: string;
@@ -148,6 +149,16 @@ export type PermissionCriteria<TQuery> =
   | NotCriteria<TQuery>
   | TQuery;
 
+/**
+ * A parameter to a permission rule.
+ */
+export type PermissionRuleParam = undefined | JsonPrimitive | JsonPrimitive[];
+
+/**
+ * Types that can be used as parameters to permission rules.
+ */
+export type PermissionRuleParams = Record<string, PermissionRuleParam>;
+
 /**
  * An individual request sent to the permission backend.
  * @public
diff --git a/plugins/permission-common/src/types/index.ts b/plugins/permission-common/src/types/index.ts
index f244a70b1a..5702f47c1c 100644
--- a/plugins/permission-common/src/types/index.ts
+++ b/plugins/permission-common/src/types/index.ts
@@ -33,6 +33,8 @@ export type {
   PolicyDecision,
   PermissionCondition,
   PermissionCriteria,
+  PermissionRuleParam,
+  PermissionRuleParams,
   AllOfCriteria,
   AnyOfCriteria,
   NotCriteria,
diff --git a/plugins/permission-node/src/integration/createConditionExports.test.ts b/plugins/permission-node/src/integration/createConditionExports.test.ts
index a989206fdd..59639f5119 100644
--- a/plugins/permission-node/src/integration/createConditionExports.test.ts
+++ b/plugins/permission-node/src/integration/createConditionExports.test.ts
@@ -46,7 +46,7 @@ const testIntegration = () =>
         description: 'Test rule 2',
         resourceType: 'test-resource',
         schema: z.object({
-          foo: z.object({}),
+          foo: z.string(),
         }),
         apply: (_resource: any) => false,
         toQuery: params => ({
@@ -76,11 +76,11 @@ describe('createConditionExports', () => {
         },
       });
 
-      expect(conditions.testRule2({ foo: { baz: 'quux' } })).toEqual({
+      expect(conditions.testRule2({ foo: 'baz' })).toEqual({
         rule: 'testRule2',
         resourceType: 'test-resource',
         params: {
-          foo: { baz: 'quux' },
+          foo: 'baz',
         },
       });
     });
diff --git a/plugins/permission-node/src/integration/createConditionFactory.ts b/plugins/permission-node/src/integration/createConditionFactory.ts
index 5b499ab512..8edeb6230f 100644
--- a/plugins/permission-node/src/integration/createConditionFactory.ts
+++ b/plugins/permission-node/src/integration/createConditionFactory.ts
@@ -14,7 +14,10 @@
  * limitations under the License.
  */
 
-import { PermissionCondition } from '@backstage/plugin-permission-common';
+import {
+  PermissionCondition,
+  PermissionRuleParams,
+} from '@backstage/plugin-permission-common';
 import { PermissionRule } from '../types';
 
 /**
@@ -34,7 +37,10 @@ import { PermissionRule } from '../types';
  * @public
  */
 export const createConditionFactory =
-  <TResourceType extends string, TParams extends Record<string, unknown>>(
+  <
+    TResourceType extends string,
+    TParams extends PermissionRuleParams = PermissionRuleParams,
+  >(
     rule: PermissionRule<unknown, unknown, TResourceType, TParams>,
   ) =>
   (params: TParams): PermissionCondition<TResourceType, TParams> => ({
diff --git a/plugins/permission-node/src/integration/createConditionTransformer.test.ts b/plugins/permission-node/src/integration/createConditionTransformer.test.ts
index 5021b7766d..0544ff3ef8 100644
--- a/plugins/permission-node/src/integration/createConditionTransformer.test.ts
+++ b/plugins/permission-node/src/integration/createConditionTransformer.test.ts
@@ -39,10 +39,10 @@ const transformConditions = createConditionTransformer([
     description: 'Test rule 2',
     resourceType: 'test-resource',
     schema: z.object({
-      foo: z.object({}),
+      foo: z.string(),
     }),
     apply: jest.fn(),
-    toQuery: jest.fn(({ foo }) => `test-rule-2:${JSON.stringify(foo)}`),
+    toQuery: jest.fn(({ foo }) => `test-rule-2:${foo}`),
   }),
 ]);
 
@@ -67,10 +67,10 @@ describe('createConditionTransformer', () => {
         rule: 'test-rule-2',
         resourceType: 'test-resource',
         params: {
-          foo: { foo: 0 },
+          foo: '0',
         },
       },
-      expectedResult: 'test-rule-2:{"foo":0}',
+      expectedResult: 'test-rule-2:0',
     },
     {
       conditions: {
@@ -87,13 +87,13 @@ describe('createConditionTransformer', () => {
             rule: 'test-rule-2',
             resourceType: 'test-resource',
             params: {
-              foo: {},
+              foo: 'b',
             },
           },
         ],
       },
       expectedResult: {
-        anyOf: ['test-rule-1:a/1', 'test-rule-2:{}'],
+        anyOf: ['test-rule-1:a/1', 'test-rule-2:b'],
       },
     },
     {
@@ -111,13 +111,13 @@ describe('createConditionTransformer', () => {
             rule: 'test-rule-2',
             resourceType: 'test-resource',
             params: {
-              foo: {},
+              foo: 'b',
             },
           },
         ],
       },
       expectedResult: {
-        allOf: ['test-rule-1:a/1', 'test-rule-2:{}'],
+        allOf: ['test-rule-1:a/1', 'test-rule-2:b'],
       },
     },
     {
@@ -126,12 +126,12 @@ describe('createConditionTransformer', () => {
           rule: 'test-rule-2',
           resourceType: 'test-resource',
           params: {
-            foo: {},
+            foo: 'a',
           },
         },
       },
       expectedResult: {
-        not: 'test-rule-2:{}',
+        not: 'test-rule-2:a',
       },
     },
     {
@@ -151,7 +151,7 @@ describe('createConditionTransformer', () => {
                 rule: 'test-rule-2',
                 resourceType: 'test-resource',
                 params: {
-                  foo: {},
+                  foo: 'b',
                 },
               },
             ],
@@ -171,9 +171,7 @@ describe('createConditionTransformer', () => {
                   rule: 'test-rule-2',
                   resourceType: 'test-resource',
                   params: {
-                    foo: {
-                      c: 3,
-                    },
+                    foo: 'c',
                   },
                 },
               ],
@@ -184,11 +182,11 @@ describe('createConditionTransformer', () => {
       expectedResult: {
         allOf: [
           {
-            anyOf: ['test-rule-1:a/1', 'test-rule-2:{}'],
+            anyOf: ['test-rule-1:a/1', 'test-rule-2:b'],
           },
           {
             not: {
-              allOf: ['test-rule-1:b/2', 'test-rule-2:{"c":3}'],
+              allOf: ['test-rule-1:b/2', 'test-rule-2:c'],
             },
           },
         ],
@@ -211,9 +209,7 @@ describe('createConditionTransformer', () => {
                 rule: 'test-rule-2',
                 resourceType: 'test-resource',
                 params: {
-                  foo: {
-                    b: 2,
-                  },
+                  foo: 'b',
                 },
               },
             ],
@@ -234,9 +230,7 @@ describe('createConditionTransformer', () => {
                     rule: 'test-rule-2',
                     resourceType: 'test-resource',
                     params: {
-                      foo: {
-                        d: 4,
-                      },
+                      foo: 'd',
                     },
                   },
                 },
@@ -248,11 +242,11 @@ describe('createConditionTransformer', () => {
       expectedResult: {
         allOf: [
           {
-            anyOf: ['test-rule-1:a/1', 'test-rule-2:{"b":2}'],
+            anyOf: ['test-rule-1:a/1', 'test-rule-2:b'],
           },
           {
             not: {
-              allOf: ['test-rule-1:c/3', { not: 'test-rule-2:{"d":4}' }],
+              allOf: ['test-rule-1:c/3', { not: 'test-rule-2:d' }],
             },
           },
         ],
diff --git a/plugins/permission-node/src/integration/createPermissionIntegrationRouter.test.ts b/plugins/permission-node/src/integration/createPermissionIntegrationRouter.test.ts
index 99e0da8287..adfa57b863 100644
--- a/plugins/permission-node/src/integration/createPermissionIntegrationRouter.test.ts
+++ b/plugins/permission-node/src/integration/createPermissionIntegrationRouter.test.ts
@@ -53,7 +53,7 @@ const testRule2 = createPermissionRule({
   description: 'Test rule 2',
   resourceType: 'test-resource',
   schema: z.object({
-    foo: z.object({}).describe('foo'),
+    foo: z.string().describe('foo'),
   }),
   apply: (_resource: any, _foo) => false,
   toQuery: _foo => ({}),
@@ -105,7 +105,7 @@ describe('createPermissionIntegrationRouter', () => {
           {
             rule: 'test-rule-2',
             resourceType: 'test-resource',
-            params: { foo: {} },
+            params: { foo: 'b' },
           },
         ],
       },
@@ -114,7 +114,7 @@ describe('createPermissionIntegrationRouter', () => {
           rule: 'test-rule-2',
           resourceType: 'test-resource',
           params: {
-            foo: {},
+            foo: 'c',
           },
         },
       },
@@ -134,7 +134,7 @@ describe('createPermissionIntegrationRouter', () => {
                 rule: 'test-rule-2',
                 resourceType: 'test-resource',
                 params: {
-                  foo: {},
+                  foo: 'b',
                 },
               },
             ],
@@ -154,7 +154,7 @@ describe('createPermissionIntegrationRouter', () => {
                   rule: 'test-rule-2',
                   resourceType: 'test-resource',
                   params: {
-                    foo: { c: 3 },
+                    foo: 'c',
                   },
                 },
               ],
@@ -192,7 +192,7 @@ describe('createPermissionIntegrationRouter', () => {
         rule: 'test-rule-2',
         resourceType: 'test-resource',
         params: {
-          foo: { foo: 0 },
+          foo: 'a',
         },
       },
       {
@@ -208,7 +208,7 @@ describe('createPermissionIntegrationRouter', () => {
           {
             rule: 'test-rule-2',
             resourceType: 'test-resource',
-            params: { foo: {} },
+            params: { foo: 'b' },
           },
         ],
       },
@@ -228,7 +228,7 @@ describe('createPermissionIntegrationRouter', () => {
                 rule: 'test-rule-2',
                 resourceType: 'test-resource',
                 params: {
-                  foo: { b: 2 },
+                  foo: 'b',
                 },
               },
             ],
@@ -249,7 +249,7 @@ describe('createPermissionIntegrationRouter', () => {
                     rule: 'test-rule-2',
                     resourceType: 'test-resource',
                     params: {
-                      foo: { d: 4 },
+                      foo: 'd',
                     },
                   },
                 },
@@ -310,7 +310,7 @@ describe('createPermissionIntegrationRouter', () => {
                   rule: 'test-rule-2',
                   resourceType: 'test-resource',
                   params: {
-                    foo: {},
+                    foo: 'b',
                   },
                 },
               },
@@ -338,7 +338,7 @@ describe('createPermissionIntegrationRouter', () => {
                     rule: 'test-rule-2',
                     resourceType: 'test-resource',
                     params: {
-                      foo: {},
+                      foo: 'c',
                     },
                   },
                 },
@@ -361,7 +361,7 @@ describe('createPermissionIntegrationRouter', () => {
                       rule: 'test-rule-2',
                       resourceType: 'test-resource',
                       params: {
-                        foo: {},
+                        foo: 'd',
                       },
                     },
                   ],
@@ -628,10 +628,8 @@ describe('createPermissionIntegrationRouter', () => {
               additionalProperties: false,
               properties: {
                 foo: {
-                  additionalProperties: false,
                   description: 'foo',
-                  properties: {},
-                  type: 'object',
+                  type: 'string',
                 },
               },
               required: ['foo'],
diff --git a/plugins/permission-node/src/integration/createPermissionIntegrationRouter.ts b/plugins/permission-node/src/integration/createPermissionIntegrationRouter.ts
index 7f355467c3..a01006c194 100644
--- a/plugins/permission-node/src/integration/createPermissionIntegrationRouter.ts
+++ b/plugins/permission-node/src/integration/createPermissionIntegrationRouter.ts
@@ -46,7 +46,7 @@ const permissionCriteriaSchema: z.ZodSchema<
     z.object({
       rule: z.string(),
       resourceType: z.string(),
-      params: z.record(z.unknown()),
+      params: z.record(z.any()),
     }),
   ]),
 );
diff --git a/plugins/permission-node/src/integration/createPermissionRule.ts b/plugins/permission-node/src/integration/createPermissionRule.ts
index ef84a5a26f..ea2e37a671 100644
--- a/plugins/permission-node/src/integration/createPermissionRule.ts
+++ b/plugins/permission-node/src/integration/createPermissionRule.ts
@@ -14,6 +14,7 @@
  * limitations under the License.
  */
 
+import { PermissionRuleParams } from '@backstage/plugin-permission-common';
 import { PermissionRule } from '../types';
 
 /**
@@ -25,7 +26,7 @@ export const createPermissionRule = <
   TResource,
   TQuery,
   TResourceType extends string,
-  TParams extends Record<string, unknown>,
+  TParams extends PermissionRuleParams = PermissionRuleParams,
 >(
   rule: PermissionRule<TResource, TQuery, TResourceType, TParams>,
 ) => rule;
@@ -40,7 +41,7 @@ export const createPermissionRule = <
  */
 export const makeCreatePermissionRule =
   <TResource, TQuery, TResourceType extends string>() =>
-  <TParams extends Record<string, unknown>>(
+  <TParams extends PermissionRuleParams = PermissionRuleParams>(
     rule: PermissionRule<TResource, TQuery, TResourceType, TParams>,
   ) =>
     createPermissionRule(rule);
diff --git a/plugins/permission-node/src/types.ts b/plugins/permission-node/src/types.ts
index 6d39d7f922..34ff52391a 100644
--- a/plugins/permission-node/src/types.ts
+++ b/plugins/permission-node/src/types.ts
@@ -14,7 +14,10 @@
  * limitations under the License.
  */
 
-import type { PermissionCriteria } from '@backstage/plugin-permission-common';
+import type {
+  PermissionCriteria,
+  PermissionRuleParams,
+} from '@backstage/plugin-permission-common';
 import { z } from 'zod';
 
 /**
@@ -45,7 +48,7 @@ export type PermissionRule<
   TResource,
   TQuery,
   TResourceType extends string,
-  TParams extends Record<string, unknown> = Record<string, unknown>,
+  TParams extends PermissionRuleParams = PermissionRuleParams,
   TSchema extends z.ZodType = z.ZodObject<{
     // Parameters can be optional, however we we want to make sure that the
     // parameters are always present in the schema, even if they are undefined.
diff --git a/yarn.lock b/yarn.lock
index bef0e188c6..168ca96586 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -6334,6 +6334,7 @@ __metadata:
     "@backstage/cli": "workspace:^"
     "@backstage/config": "workspace:^"
     "@backstage/errors": "workspace:^"
+    "@backstage/types": "workspace:^"
     cross-fetch: ^3.1.5
     msw: ^0.47.0
     uuid: ^8.0.0