diff --git a/x-pack/test/api_integration/deployment_agnostic/apis/observability/ai_assistant/conversations/conversations.spec.ts b/x-pack/test/api_integration/deployment_agnostic/apis/observability/ai_assistant/conversations/conversations.spec.ts
new file mode 100644
index 0000000000000..5040285a66753
--- /dev/null
+++ b/x-pack/test/api_integration/deployment_agnostic/apis/observability/ai_assistant/conversations/conversations.spec.ts
@@ -0,0 +1,263 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License
+ * 2.0; you may not use this file except in compliance with the Elastic License
+ * 2.0.
+ */
+
+import expect from '@kbn/expect';
+import { merge, omit } from 'lodash';
+import {
+  type ConversationCreateRequest,
+  type ConversationUpdateRequest,
+  MessageRole,
+} from '@kbn/observability-ai-assistant-plugin/common/types';
+import type { SupertestReturnType } from '../../../../services/observability_ai_assistant_api';
+import type { DeploymentAgnosticFtrProviderContext } from '../../../../ftr_provider_context';
+
+export default function ApiTest({ getService }: DeploymentAgnosticFtrProviderContext) {
+  const observabilityAIAssistantAPIClient = getService('observabilityAIAssistantApi');
+
+  const conversationCreate: ConversationCreateRequest = {
+    '@timestamp': new Date().toISOString(),
+    conversation: {
+      title: 'My title',
+    },
+    labels: {},
+    numeric_labels: {},
+    messages: [
+      {
+        '@timestamp': new Date().toISOString(),
+        message: {
+          role: MessageRole.User,
+          content: 'My message',
+        },
+      },
+    ],
+    public: false,
+  };
+
+  const conversationUpdate: ConversationUpdateRequest = merge({}, conversationCreate, {
+    conversation: {
+      id: '<conversationCreate.id>',
+      title: 'My updated title',
+    },
+  });
+
+  describe('Conversations', () => {
+    describe('without conversations', () => {
+      it('returns no conversations when listing', async () => {
+        const { status, body } = await observabilityAIAssistantAPIClient.editor({
+          endpoint: 'POST /internal/observability_ai_assistant/conversations',
+        });
+
+        expect(status).to.be(200);
+
+        expect(body).to.eql({ conversations: [] });
+      });
+
+      it('returns a 404 for updating conversations', async () => {
+        try {
+          await observabilityAIAssistantAPIClient.editor({
+            endpoint: 'PUT /internal/observability_ai_assistant/conversation/{conversationId}',
+            params: {
+              path: {
+                conversationId: 'non-existing-conversation-id',
+              },
+              body: {
+                conversation: conversationUpdate,
+              },
+            },
+          });
+        } catch (error) {
+          expect(error.status).to.be(404);
+        }
+      });
+
+      it('returns a 404 for retrieving a conversation', async () => {
+        try {
+          await observabilityAIAssistantAPIClient.editor({
+            endpoint: 'GET /internal/observability_ai_assistant/conversation/{conversationId}',
+            params: {
+              path: {
+                conversationId: 'my-conversation-id',
+              },
+            },
+          });
+        } catch (error) {
+          expect(error.status).to.be(404);
+        }
+      });
+    });
+
+    describe('when creating a conversation with the write user', () => {
+      let createResponse: Awaited<
+        SupertestReturnType<'POST /internal/observability_ai_assistant/conversation'>
+      >;
+      before(async () => {
+        createResponse = await observabilityAIAssistantAPIClient.editor({
+          endpoint: 'POST /internal/observability_ai_assistant/conversation',
+          params: {
+            body: {
+              conversation: conversationCreate,
+            },
+          },
+        });
+        expect(createResponse.status).to.be(200);
+      });
+
+      after(async () => {
+        const { status } = await observabilityAIAssistantAPIClient.editor({
+          endpoint: 'DELETE /internal/observability_ai_assistant/conversation/{conversationId}',
+          params: {
+            path: {
+              conversationId: createResponse.body.conversation.id,
+            },
+          },
+        });
+        expect(status).to.be(200);
+
+        try {
+          await observabilityAIAssistantAPIClient.editor({
+            endpoint: 'GET /internal/observability_ai_assistant/conversation/{conversationId}',
+            params: {
+              path: {
+                conversationId: createResponse.body.conversation.id,
+              },
+            },
+          });
+        } catch (error) {
+          expect(error.status).to.be(404);
+        }
+      });
+
+      it('returns the conversation', () => {
+        // delete user from response to avoid comparing it as it will be different in MKI
+        // delete createResponse.body.user;
+        expect(createResponse.body).to.eql({
+          '@timestamp': createResponse.body['@timestamp'],
+          conversation: {
+            id: createResponse.body.conversation.id,
+            last_updated: createResponse.body.conversation.last_updated,
+            title: conversationCreate.conversation.title,
+          },
+          labels: conversationCreate.labels,
+          numeric_labels: conversationCreate.numeric_labels,
+          messages: conversationCreate.messages,
+          namespace: 'default',
+          public: conversationCreate.public,
+          user: {
+            id: 'u_gf3TRV5WWjD0PQCcTzkUyRE8By8uUt90gK-rT9ZPhA4_0',
+            name: 'elastic_editor',
+          },
+        });
+      });
+
+      it('returns a 404 for updating a non-existing conversation', async () => {
+        try {
+          await observabilityAIAssistantAPIClient.editor({
+            endpoint: 'PUT /internal/observability_ai_assistant/conversation/{conversationId}',
+            params: {
+              path: {
+                conversationId: 'non-existing-conversation-id',
+              },
+              body: {
+                conversation: conversationUpdate,
+              },
+            },
+          });
+        } catch (error) {
+          expect(error.status).to.be(404);
+        }
+      });
+
+      it('returns a 404 for retrieving a non-existing conversation', async () => {
+        try {
+          await observabilityAIAssistantAPIClient.editor({
+            endpoint: 'GET /internal/observability_ai_assistant/conversation/{conversationId}',
+            params: {
+              path: {
+                conversationId: 'non-existing-conversation-id',
+              },
+            },
+          });
+        } catch (error) {
+          expect(error.status).to.be(404);
+        }
+      });
+
+      it('returns the conversation that was created', async () => {
+        const response = await observabilityAIAssistantAPIClient.editor({
+          endpoint: 'GET /internal/observability_ai_assistant/conversation/{conversationId}',
+          params: {
+            path: {
+              conversationId: createResponse.body.conversation.id,
+            },
+          },
+        });
+
+        expect(response.status).to.be(200);
+
+        expect(response.body).to.eql(createResponse.body);
+      });
+
+      it('returns the created conversation when listing', async () => {
+        const response = await observabilityAIAssistantAPIClient.editor({
+          endpoint: 'POST /internal/observability_ai_assistant/conversations',
+        });
+
+        expect(response.status).to.be(200);
+
+        expect(response.body.conversations[0]).to.eql(createResponse.body);
+      });
+      // TODO
+      it.skip('returns a 404 when reading it with another user', () => {});
+
+      describe('after updating', () => {
+        let updateResponse: Awaited<
+          SupertestReturnType<'PUT /internal/observability_ai_assistant/conversation/{conversationId}'>
+        >;
+
+        before(async () => {
+          updateResponse = await observabilityAIAssistantAPIClient.editor({
+            endpoint: 'PUT /internal/observability_ai_assistant/conversation/{conversationId}',
+            params: {
+              path: {
+                conversationId: createResponse.body.conversation.id,
+              },
+              body: {
+                conversation: merge(omit(conversationUpdate, 'conversation.id'), {
+                  conversation: { id: createResponse.body.conversation.id },
+                }),
+              },
+            },
+          });
+          expect(updateResponse.status).to.be(200);
+        });
+
+        it('returns the updated conversation as response', async () => {
+          expect(updateResponse.body.conversation.title).to.eql(
+            conversationUpdate.conversation.title
+          );
+        });
+
+        it('returns the updated conversation after get', async () => {
+          const updateAfterCreateResponse = await observabilityAIAssistantAPIClient.editor({
+            endpoint: 'GET /internal/observability_ai_assistant/conversation/{conversationId}',
+            params: {
+              path: {
+                conversationId: createResponse.body.conversation.id,
+              },
+            },
+          });
+
+          expect(updateAfterCreateResponse.status).to.be(200);
+
+          expect(updateAfterCreateResponse.body.conversation.title).to.eql(
+            conversationUpdate.conversation.title
+          );
+        });
+      });
+    });
+  });
+}
diff --git a/x-pack/test/api_integration/deployment_agnostic/apis/observability/ai_assistant/conversations/index.ts b/x-pack/test/api_integration/deployment_agnostic/apis/observability/ai_assistant/conversations/index.ts
new file mode 100644
index 0000000000000..95d26566af6b5
--- /dev/null
+++ b/x-pack/test/api_integration/deployment_agnostic/apis/observability/ai_assistant/conversations/index.ts
@@ -0,0 +1,14 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License
+ * 2.0; you may not use this file except in compliance with the Elastic License
+ * 2.0.
+ */
+
+import type { DeploymentAgnosticFtrProviderContext } from '../../../../ftr_provider_context';
+
+export default function ({ loadTestFile }: DeploymentAgnosticFtrProviderContext) {
+  describe('conversations', () => {
+    loadTestFile(require.resolve('./conversations.spec.ts'));
+  });
+}
diff --git a/x-pack/test/api_integration/deployment_agnostic/apis/observability/ai_assistant/index.ts b/x-pack/test/api_integration/deployment_agnostic/apis/observability/ai_assistant/index.ts
new file mode 100644
index 0000000000000..37f3899436c82
--- /dev/null
+++ b/x-pack/test/api_integration/deployment_agnostic/apis/observability/ai_assistant/index.ts
@@ -0,0 +1,16 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License
+ * 2.0; you may not use this file except in compliance with the Elastic License
+ * 2.0.
+ */
+
+import type { DeploymentAgnosticFtrProviderContext } from '../../../ftr_provider_context';
+
+export default function aiAssistantApiIntegrationTests({
+  loadTestFile,
+}: DeploymentAgnosticFtrProviderContext) {
+  describe('observability AI Assistant', function () {
+    loadTestFile(require.resolve('./conversations'));
+  });
+}
diff --git a/x-pack/test/api_integration/deployment_agnostic/configs/serverless/oblt.index.ts b/x-pack/test/api_integration/deployment_agnostic/configs/serverless/oblt.index.ts
index 7544d7d90f1d5..edd82fc62dca6 100644
--- a/x-pack/test/api_integration/deployment_agnostic/configs/serverless/oblt.index.ts
+++ b/x-pack/test/api_integration/deployment_agnostic/configs/serverless/oblt.index.ts
@@ -21,5 +21,6 @@ export default function ({ loadTestFile }: DeploymentAgnosticFtrProviderContext)
     loadTestFile(require.resolve('../../apis/saved_objects_management'));
     loadTestFile(require.resolve('../../apis/observability/slo'));
     loadTestFile(require.resolve('../../apis/observability/synthetics'));
+    loadTestFile(require.resolve('../../apis/observability/ai_assistant'));
   });
 }
diff --git a/x-pack/test/api_integration/deployment_agnostic/configs/stateful/oblt.index.ts b/x-pack/test/api_integration/deployment_agnostic/configs/stateful/oblt.index.ts
index 4f666fc5b3ebe..4f0c42e12b1fb 100644
--- a/x-pack/test/api_integration/deployment_agnostic/configs/stateful/oblt.index.ts
+++ b/x-pack/test/api_integration/deployment_agnostic/configs/stateful/oblt.index.ts
@@ -15,5 +15,6 @@ export default function ({ loadTestFile }: DeploymentAgnosticFtrProviderContext)
     loadTestFile(require.resolve('../../apis/observability/slo'));
     loadTestFile(require.resolve('../../apis/observability/synthetics'));
     loadTestFile(require.resolve('../../apis/observability/infra'));
+    loadTestFile(require.resolve('../../apis/observability/ai_assistant'));
   });
 }