diff --git a/eslint.config.js b/eslint.config.js
index a06437e..7a41a5b 100644
--- a/eslint.config.js
+++ b/eslint.config.js
@@ -18,6 +18,8 @@ export default [
         setTimeout: 'readonly',
         NodeJS: 'readonly',
         require: 'readonly',
+        fetch: 'readonly',
+        URLSearchParams: 'readonly',
       },
     },
     plugins: {
@@ -50,6 +52,8 @@ export default [
         __dirname: 'readonly',
         clearTimeout: 'readonly',
         setTimeout: 'readonly',
+        global: 'readonly',
+        fetch: 'readonly',
       },
     },
     plugins: {
diff --git a/src/__tests__/branches.test.ts b/src/__tests__/branches.test.ts
index 71903aa..e9cbfa6 100644
--- a/src/__tests__/branches.test.ts
+++ b/src/__tests__/branches.test.ts
@@ -6,6 +6,22 @@ import {
 } from "../shared/elevenlabs-api";
 import { ElevenLabsClient } from "@elevenlabs/elevenlabs-js";
 
+const TEST_CTX = { apiKey: "test-key", baseUrl: "https://api.test" };
+
+const realFetch = global.fetch;
+afterEach(() => {
+  global.fetch = realFetch;
+});
+
+function mockFetch(response: Record<string, unknown>): jest.Mock {
+  const fetchMock = jest.fn().mockResolvedValue({
+    ok: true,
+    json: async () => response,
+  });
+  global.fetch = fetchMock as unknown as typeof fetch;
+  return fetchMock;
+}
+
 describe("Agent branch support", () => {
   function makeMockClient(opts: {
     branches?: Array<{
@@ -190,14 +206,14 @@ describe("Agent branch support", () => {
   });
 
   describe("updateAgentApi with branchId", () => {
-    it("should not include branchId in payload when not provided", async () => {
-      const client = makeMockClient();
+    it("should not include branch_id query param when not provided", async () => {
+      const fetchMock = mockFetch({ agent_id: "agent_123" });
       const conversationConfig = {
         agent: { prompt: { prompt: "hi", temperature: 0 } },
       } as unknown as Record<string, unknown>;
 
       await updateAgentApi(
-        client,
+        TEST_CTX,
         "agent_123",
         "Test Agent",
         conversationConfig,
@@ -207,21 +223,18 @@ describe("Agent branch support", () => {
         "v1.0"
       );
 
-      const [, payload] = (
-        client.conversationalAi.agents.update as jest.Mock
-      ).mock.calls[0];
-
-      expect(payload.branchId).toBeUndefined();
+      const [url] = fetchMock.mock.calls[0];
+      expect(url).toBe("https://api.test/v1/convai/agents/agent_123");
     });
 
-    it("should include branchId in payload when provided", async () => {
-      const client = makeMockClient();
+    it("should include branch_id query param when provided", async () => {
+      const fetchMock = mockFetch({ agent_id: "agent_123" });
       const conversationConfig = {
         agent: { prompt: { prompt: "hi", temperature: 0 } },
       } as unknown as Record<string, unknown>;
 
       await updateAgentApi(
-        client,
+        TEST_CTX,
         "agent_123",
         "Test Agent",
         conversationConfig,
@@ -232,22 +245,20 @@ describe("Agent branch support", () => {
         "agtbrch_feat456"
       );
 
-      const [agentId, payload] = (
-        client.conversationalAi.agents.update as jest.Mock
-      ).mock.calls[0];
-
-      expect(agentId).toBe("agent_123");
-      expect(payload.branchId).toBe("agtbrch_feat456");
+      const [url] = fetchMock.mock.calls[0];
+      expect(url).toBe(
+        "https://api.test/v1/convai/agents/agent_123?branch_id=agtbrch_feat456"
+      );
     });
 
     it("should return branchId from API response", async () => {
-      const client = makeMockClient();
+      mockFetch({ agent_id: "agent_123", branch_id: "agtbrch_feat" });
       const conversationConfig = {
         agent: { prompt: { prompt: "hi", temperature: 0 } },
       } as unknown as Record<string, unknown>;
 
       const result = await updateAgentApi(
-        client,
+        TEST_CTX,
         "agent_123",
         "Test Agent",
         conversationConfig,
diff --git a/src/__tests__/casing.test.ts b/src/__tests__/casing.test.ts
index 091123b..1fa1191 100644
--- a/src/__tests__/casing.test.ts
+++ b/src/__tests__/casing.test.ts
@@ -8,10 +8,28 @@ import {
 } from "../shared/elevenlabs-api";
 import { ElevenLabsClient } from "@elevenlabs/elevenlabs-js";
 
+const TEST_CTX = { apiKey: "test-key", baseUrl: "https://api.test" };
+
+const realFetch = global.fetch;
+afterEach(() => {
+  global.fetch = realFetch;
+});
+
+function mockFetch(response: Record<string, unknown> = { agent_id: "agent_123" }): jest.Mock {
+  const fetchMock = jest.fn().mockResolvedValue({
+    ok: true,
+    json: async () => response,
+  });
+  global.fetch = fetchMock as unknown as typeof fetch;
+  return fetchMock;
+}
+
+function sentBody(fetchMock: jest.Mock): Record<string, any> {
+  return JSON.parse(fetchMock.mock.calls[0][1].body as string);
+}
+
 describe("Key casing normalization", () => {
   function makeMockClient() {
-    const create = jest.fn().mockResolvedValue({ agentId: "agent_123" });
-    const update = jest.fn().mockResolvedValue({ agentId: "agent_123" });
     const get = jest.fn().mockResolvedValue({
       agentId: "agent_123",
       name: "Test Agent",
@@ -34,13 +52,13 @@ describe("Key casing normalization", () => {
 
     return {
       conversationalAi: {
-        agents: { create, update, get },
+        agents: { get },
       },
     } as unknown as ElevenLabsClient;
   }
 
-  it("createAgentApi camelizes outbound conversation_config and platform_settings", async () => {
-    const client = makeMockClient();
+  it("createAgentApi sends conversation_config and platform_settings as snake_case wire JSON", async () => {
+    const fetchMock = mockFetch();
     const conversation_config = {
       conversation: {
         client_events: ["audio", "interruption"],
@@ -52,7 +70,7 @@ describe("Key casing normalization", () => {
     } as unknown as Record<string, unknown>;
 
     await createAgentApi(
-      client,
+      TEST_CTX,
       "Name",
       conversation_config,
       platform_settings,
@@ -60,31 +78,29 @@ describe("Key casing normalization", () => {
       ["prod"]
     );
 
-    expect(client.conversationalAi.agents.create).toHaveBeenCalledTimes(1);
-    const [, payload] = [
-      (client.conversationalAi.agents.create as jest.Mock).mock.calls[0][0]
-        .name,
-      (client.conversationalAi.agents.create as jest.Mock).mock.calls[0][0],
-    ];
+    expect(fetchMock).toHaveBeenCalledTimes(1);
+    const [url, init] = fetchMock.mock.calls[0];
+    expect(url).toBe("https://api.test/v1/convai/agents/create");
+    expect(init.method).toBe("POST");
 
-    expect(payload).toEqual(
+    expect(sentBody(fetchMock)).toEqual(
       expect.objectContaining({
         name: "Name",
-        conversationConfig: expect.objectContaining({
+        conversation_config: expect.objectContaining({
           conversation: expect.objectContaining({
-            clientEvents: ["audio", "interruption"],
+            client_events: ["audio", "interruption"],
           }),
         }),
-        platformSettings: expect.objectContaining({
-          widget: expect.objectContaining({ textInputEnabled: true }),
+        platform_settings: expect.objectContaining({
+          widget: expect.objectContaining({ text_input_enabled: true }),
         }),
         tags: ["prod"],
       })
     );
   });
 
-  it("updateAgentApi camelizes outbound conversation_config", async () => {
-    const client = makeMockClient();
+  it("updateAgentApi sends conversation_config as snake_case wire JSON", async () => {
+    const fetchMock = mockFetch();
     const conversation_config = {
       conversation: {
         client_events: ["audio", "agent_response"],
@@ -92,7 +108,7 @@ describe("Key casing normalization", () => {
     } as unknown as Record<string, unknown>;
 
     await updateAgentApi(
-      client,
+      TEST_CTX,
       "agent_123",
       "Name",
       conversation_config,
@@ -101,17 +117,16 @@ describe("Key casing normalization", () => {
       ["prod"]
     );
 
-    expect(client.conversationalAi.agents.update).toHaveBeenCalledTimes(1);
-    const [agentId, payload] = (
-      client.conversationalAi.agents.update as jest.Mock
-    ).mock.calls[0];
-    expect(agentId).toBe("agent_123");
-    expect(payload).toEqual(
+    expect(fetchMock).toHaveBeenCalledTimes(1);
+    const [url, init] = fetchMock.mock.calls[0];
+    expect(url).toBe("https://api.test/v1/convai/agents/agent_123");
+    expect(init.method).toBe("PATCH");
+    expect(sentBody(fetchMock)).toEqual(
       expect.objectContaining({
         name: "Name",
-        conversationConfig: expect.objectContaining({
+        conversation_config: expect.objectContaining({
           conversation: expect.objectContaining({
-            clientEvents: ["audio", "agent_response"],
+            client_events: ["audio", "agent_response"],
           }),
         }),
         tags: ["prod"],
@@ -119,6 +134,22 @@ describe("Key casing normalization", () => {
     );
   });
 
+  it("createAgentApi normalizes hand-written camelCase keys to snake_case on the wire", async () => {
+    const fetchMock = mockFetch();
+    const conversation_config = {
+      conversation: {
+        clientEvents: ["audio"],
+      },
+      agent: { prompt: { prompt: "hi", temperature: 0 } },
+    } as unknown as Record<string, unknown>;
+
+    await createAgentApi(TEST_CTX, "Name", conversation_config, undefined, undefined, []);
+
+    const body = sentBody(fetchMock);
+    expect(body.conversation_config.conversation).toHaveProperty("client_events");
+    expect(body.conversation_config.conversation).not.toHaveProperty("clientEvents");
+  });
+
   it("getAgentApi snake_cases inbound response for writing to disk", async () => {
     const client = makeMockClient();
     const response = await getAgentApi(client, "agent_123");
@@ -143,7 +174,7 @@ describe("Key casing normalization", () => {
   });
 
   it("createAgentApi removes deprecated 'tools' field when 'tool_ids' is present", async () => {
-    const client = makeMockClient();
+    const fetchMock = mockFetch();
     const conversation_config = {
       conversation: {
         client_events: ["audio"],
@@ -161,7 +192,7 @@ describe("Key casing normalization", () => {
     } as unknown as Record<string, unknown>;
 
     await createAgentApi(
-      client,
+      TEST_CTX,
       "Agent with Tools",
       conversation_config,
       undefined,
@@ -169,17 +200,16 @@ describe("Key casing normalization", () => {
       []
     );
 
-    expect(client.conversationalAi.agents.create).toHaveBeenCalledTimes(1);
-    const payload = (client.conversationalAi.agents.create as jest.Mock).mock.calls[0][0];
+    const body = sentBody(fetchMock);
 
-    // Verify that 'tools' field is removed but 'toolIds' is present
-    expect(payload.conversationConfig.agent.prompt).not.toHaveProperty("tools");
-    expect(payload.conversationConfig.agent.prompt).toHaveProperty("toolIds");
-    expect(payload.conversationConfig.agent.prompt.toolIds).toEqual(["tool_123", "tool_456"]);
+    // Verify that 'tools' field is removed but 'tool_ids' is present
+    expect(body.conversation_config.agent.prompt).not.toHaveProperty("tools");
+    expect(body.conversation_config.agent.prompt).toHaveProperty("tool_ids");
+    expect(body.conversation_config.agent.prompt.tool_ids).toEqual(["tool_123", "tool_456"]);
   });
 
   it("updateAgentApi removes deprecated 'tools' field when 'tool_ids' is present", async () => {
-    const client = makeMockClient();
+    const fetchMock = mockFetch();
     const conversation_config = {
       agent: {
         prompt: {
@@ -193,7 +223,7 @@ describe("Key casing normalization", () => {
     } as unknown as Record<string, unknown>;
 
     await updateAgentApi(
-      client,
+      TEST_CTX,
       "agent_123",
       "Updated Agent",
       conversation_config,
@@ -202,17 +232,16 @@ describe("Key casing normalization", () => {
       []
     );
 
-    expect(client.conversationalAi.agents.update).toHaveBeenCalledTimes(1);
-    const [, payload] = (client.conversationalAi.agents.update as jest.Mock).mock.calls[0];
+    const body = sentBody(fetchMock);
 
-    // Verify that 'tools' field is removed but 'toolIds' is present
-    expect(payload.conversationConfig.agent.prompt).not.toHaveProperty("tools");
-    expect(payload.conversationConfig.agent.prompt).toHaveProperty("toolIds");
-    expect(payload.conversationConfig.agent.prompt.toolIds).toEqual(["tool_789"]);
+    // Verify that 'tools' field is removed but 'tool_ids' is present
+    expect(body.conversation_config.agent.prompt).not.toHaveProperty("tools");
+    expect(body.conversation_config.agent.prompt).toHaveProperty("tool_ids");
+    expect(body.conversation_config.agent.prompt.tool_ids).toEqual(["tool_789"]);
   });
 
-  it("createAgentApi camelizes workflow edge conditions (forward_condition, backward_condition)", async () => {
-    const client = makeMockClient();
+  it("createAgentApi sends workflow edge conditions unchanged on the wire", async () => {
+    const fetchMock = mockFetch();
     const conversation_config = {
       agent: { prompt: { prompt: "hi", temperature: 0 } },
     } as unknown as Record<string, unknown>;
@@ -238,7 +267,7 @@ describe("Key casing normalization", () => {
     };
 
     await createAgentApi(
-      client,
+      TEST_CTX,
       "Workflow Agent",
       conversation_config,
       undefined,
@@ -246,25 +275,14 @@ describe("Key casing normalization", () => {
       []
     );
 
-    expect(client.conversationalAi.agents.create).toHaveBeenCalledTimes(1);
-    const payload = (client.conversationalAi.agents.create as jest.Mock).mock.calls[0][0];
+    const body = sentBody(fetchMock);
 
-    // Verify workflow edge identifier keys are preserved, but schema fields within are camel-cased
-    expect(payload.workflow).toBeDefined();
-    expect(payload.workflow.edges.edge_start_to_agent).toEqual({
-      source: "start_node",
-      target: "agent_node",
-      forwardCondition: { type: "unconditional" }
-    });
-    expect(payload.workflow.edges.edge_agent_to_end).toEqual({
-      source: "agent_node",
-      target: "end_node",
-      backwardCondition: { type: "result", resultKey: "success" }
-    });
+    // A pulled workflow must round-trip through push byte-for-byte
+    expect(body.workflow).toEqual(workflow);
   });
 
-  it("updateAgentApi camelizes workflow edge conditions (forward_condition, backward_condition)", async () => {
-    const client = makeMockClient();
+  it("updateAgentApi sends workflow edge conditions unchanged on the wire", async () => {
+    const fetchMock = mockFetch();
     const conversation_config = {
       agent: { prompt: { prompt: "hi", temperature: 0 } },
     } as unknown as Record<string, unknown>;
@@ -285,7 +303,7 @@ describe("Key casing normalization", () => {
     };
 
     await updateAgentApi(
-      client,
+      TEST_CTX,
       "agent_123",
       "Workflow Agent",
       conversation_config,
@@ -294,20 +312,12 @@ describe("Key casing normalization", () => {
       []
     );
 
-    expect(client.conversationalAi.agents.update).toHaveBeenCalledTimes(1);
-    const [, payload] = (client.conversationalAi.agents.update as jest.Mock).mock.calls[0];
-
-    // Verify workflow edge identifier keys are preserved, but schema fields within are camel-cased
-    expect(payload.workflow).toBeDefined();
-    expect(payload.workflow.edges.edge_start_to_agent).toEqual({
-      source: "start_node",
-      target: "agent_node",
-      forwardCondition: { type: "llm", description: "When user asks for help" }
-    });
+    const body = sentBody(fetchMock);
+    expect(body.workflow).toEqual(workflow);
   });
 
   it("createAgentApi preserves data_collection child keys (user-defined identifiers)", async () => {
-    const client = makeMockClient();
+    const fetchMock = mockFetch();
     const conversation_config = {
       agent: { prompt: { prompt: "hi", temperature: 0 } },
     } as unknown as Record<string, unknown>;
@@ -320,7 +330,7 @@ describe("Key casing normalization", () => {
     } as unknown as Record<string, unknown>;
 
     await createAgentApi(
-      client,
+      TEST_CTX,
       "Agent with data_collection",
       conversation_config,
       platform_settings,
@@ -328,23 +338,21 @@ describe("Key casing normalization", () => {
       []
     );
 
-    const payload = (client.conversationalAi.agents.create as jest.Mock).mock.calls[0][0];
+    const body = sentBody(fetchMock);
 
-    // data_collection top-level key is camelized to dataCollection (envelope convention)
-    expect(payload.platformSettings).toHaveProperty("dataCollection");
-    // Children are user-defined identifiers — must be preserved as-is (snake_case stays snake_case)
-    expect(payload.platformSettings.dataCollection).toHaveProperty("need_callback");
-    expect(payload.platformSettings.dataCollection).toHaveProperty("call_end_reason");
-    expect(payload.platformSettings.dataCollection).toHaveProperty("human_reached");
-    // Leaf values under each identifier — nested schema fields like 'type'/'description' stay as-is (no underscores to convert)
-    expect(payload.platformSettings.dataCollection.need_callback).toEqual({
+    expect(body.platform_settings).toHaveProperty("data_collection");
+    // Children are user-defined identifiers — must be preserved as-is
+    expect(body.platform_settings.data_collection).toHaveProperty("need_callback");
+    expect(body.platform_settings.data_collection).toHaveProperty("call_end_reason");
+    expect(body.platform_settings.data_collection).toHaveProperty("human_reached");
+    expect(body.platform_settings.data_collection.need_callback).toEqual({
       type: "boolean",
       description: "Whether to call back",
     });
   });
 
   it("updateAgentApi preserves data_collection child keys (user-defined identifiers)", async () => {
-    const client = makeMockClient();
+    const fetchMock = mockFetch();
     const conversation_config = {
       agent: { prompt: { prompt: "updated", temperature: 0 } },
     } as unknown as Record<string, unknown>;
@@ -355,7 +363,7 @@ describe("Key casing normalization", () => {
     } as unknown as Record<string, unknown>;
 
     await updateAgentApi(
-      client,
+      TEST_CTX,
       "agent_123",
       "Updated",
       conversation_config,
@@ -364,10 +372,10 @@ describe("Key casing normalization", () => {
       []
     );
 
-    const [, payload] = (client.conversationalAi.agents.update as jest.Mock).mock.calls[0];
+    const body = sentBody(fetchMock);
 
-    expect(payload.platformSettings).toHaveProperty("dataCollection");
-    expect(payload.platformSettings.dataCollection).toHaveProperty("need_callback");
+    expect(body.platform_settings).toHaveProperty("data_collection");
+    expect(body.platform_settings.data_collection).toHaveProperty("need_callback");
   });
 
   it("getAgentApi preserves data_collection child keys on inbound snake_case conversion", async () => {
@@ -428,7 +436,7 @@ describe("Key casing normalization", () => {
   });
 
   it("createAgentApi preserves 'tools' field when 'tool_ids' is not present", async () => {
-    const client = makeMockClient();
+    const fetchMock = mockFetch();
     const conversation_config = {
       agent: {
         prompt: {
@@ -441,7 +449,7 @@ describe("Key casing normalization", () => {
     } as unknown as Record<string, unknown>;
 
     await createAgentApi(
-      client,
+      TEST_CTX,
       "Agent with Legacy Tools",
       conversation_config,
       undefined,
@@ -449,11 +457,11 @@ describe("Key casing normalization", () => {
       []
     );
 
-    const payload = (client.conversationalAi.agents.create as jest.Mock).mock.calls[0][0];
+    const body = sentBody(fetchMock);
 
     // When tool_ids is not present, tools should be preserved
-    expect(payload.conversationConfig.agent.prompt).toHaveProperty("tools");
-    expect(payload.conversationConfig.agent.prompt.tools).toHaveLength(1);
+    expect(body.conversation_config.agent.prompt).toHaveProperty("tools");
+    expect(body.conversation_config.agent.prompt.tools).toHaveLength(1);
   });
 
   function makeToolsMockClient() {
@@ -485,8 +493,8 @@ describe("Key casing normalization", () => {
     } as unknown as ElevenLabsClient;
   }
 
-  it("createAgentApi camelizes the placeholders wrapper but preserves placeholder names", async () => {
-    const client = makeMockClient();
+  it("createAgentApi keeps the placeholders wrapper snake_case and preserves placeholder names", async () => {
+    const fetchMock = mockFetch();
     const conversation_config = {
       agent: {
         prompt: { prompt: "hi", temperature: 0 },
@@ -500,7 +508,7 @@ describe("Key casing normalization", () => {
     } as unknown as Record<string, unknown>;
 
     await createAgentApi(
-      client,
+      TEST_CTX,
       "Agent with placeholders",
       conversation_config,
       undefined,
@@ -508,21 +516,19 @@ describe("Key casing normalization", () => {
       []
     );
 
-    const payload = (client.conversationalAi.agents.create as jest.Mock).mock.calls[0][0];
-    const dynamicVariables = payload.conversationConfig.agent.dynamicVariables;
+    const body = sentBody(fetchMock);
+    const dynamicVariables = body.conversation_config.agent.dynamic_variables;
 
-    // The wrapper is a schema field: it must be camelized or the SDK strips it from the request
-    expect(dynamicVariables).toHaveProperty("dynamicVariablePlaceholders");
-    expect(dynamicVariables).not.toHaveProperty("dynamic_variable_placeholders");
+    expect(dynamicVariables).toHaveProperty("dynamic_variable_placeholders");
     // Placeholder names are user-defined identifiers, preserved as-is
-    expect(dynamicVariables.dynamicVariablePlaceholders).toEqual({
+    expect(dynamicVariables.dynamic_variable_placeholders).toEqual({
       transaction_id: "txn_default",
       verified: false,
     });
   });
 
-  it("updateAgentApi camelizes the placeholders wrapper but preserves placeholder names", async () => {
-    const client = makeMockClient();
+  it("updateAgentApi keeps the placeholders wrapper snake_case and preserves placeholder names", async () => {
+    const fetchMock = mockFetch();
     const conversation_config = {
       agent: {
         prompt: { prompt: "hi", temperature: 0 },
@@ -536,7 +542,7 @@ describe("Key casing normalization", () => {
     } as unknown as Record<string, unknown>;
 
     await updateAgentApi(
-      client,
+      TEST_CTX,
       "agent_123",
       "Updated",
       conversation_config,
@@ -545,12 +551,11 @@ describe("Key casing normalization", () => {
       []
     );
 
-    const [, payload] = (client.conversationalAi.agents.update as jest.Mock).mock.calls[0];
-    const dynamicVariables = payload.conversationConfig.agent.dynamicVariables;
+    const body = sentBody(fetchMock);
+    const dynamicVariables = body.conversation_config.agent.dynamic_variables;
 
-    expect(dynamicVariables).toHaveProperty("dynamicVariablePlaceholders");
-    expect(dynamicVariables).not.toHaveProperty("dynamic_variable_placeholders");
-    expect(dynamicVariables.dynamicVariablePlaceholders).toEqual({
+    expect(dynamicVariables).toHaveProperty("dynamic_variable_placeholders");
+    expect(dynamicVariables.dynamic_variable_placeholders).toEqual({
       transaction_id: "txn_default",
       user_name: "Jan",
     });
diff --git a/src/__tests__/versioning.test.ts b/src/__tests__/versioning.test.ts
index 43c74bc..7274579 100644
--- a/src/__tests__/versioning.test.ts
+++ b/src/__tests__/versioning.test.ts
@@ -1,18 +1,32 @@
 import { updateAgentApi, getAgentApi } from "../shared/elevenlabs-api";
 import { ElevenLabsClient } from "@elevenlabs/elevenlabs-js";
 
+const TEST_CTX = { apiKey: "test-key", baseUrl: "https://api.test" };
+
+const realFetch = global.fetch;
+afterEach(() => {
+  global.fetch = realFetch;
+});
+
+function mockFetch(response: Record<string, unknown>): jest.Mock {
+  const fetchMock = jest.fn().mockResolvedValue({
+    ok: true,
+    json: async () => response,
+  });
+  global.fetch = fetchMock as unknown as typeof fetch;
+  return fetchMock;
+}
+
+function sentBody(fetchMock: jest.Mock): Record<string, any> {
+  return JSON.parse(fetchMock.mock.calls[0][1].body as string);
+}
+
 describe("Agent versioning and branch support", () => {
   function makeMockClient(opts: {
     versionId?: string;
     branchId?: string;
     mainBranchId?: string;
   } = {}) {
-    const create = jest.fn().mockResolvedValue({ agentId: "agent_ver_123" });
-    const update = jest.fn().mockResolvedValue({
-      agentId: "agent_ver_123",
-      versionId: opts.versionId ?? "ver_abc",
-      branchId: opts.branchId ?? "branch_main",
-    });
     const get = jest.fn().mockResolvedValue({
       agentId: "agent_ver_123",
       name: "Test Agent",
@@ -28,20 +42,20 @@ describe("Agent versioning and branch support", () => {
 
     return {
       conversationalAi: {
-        agents: { create, update, get },
+        agents: { get },
       },
     } as unknown as ElevenLabsClient;
   }
 
   describe("updateAgentApi", () => {
     it("should pass versionDescription to the API", async () => {
-      const client = makeMockClient();
+      const fetchMock = mockFetch({ agent_id: "agent_ver_123" });
       const conversationConfig = {
         agent: { prompt: { prompt: "hi", temperature: 0 } },
       } as unknown as Record<string, unknown>;
 
       await updateAgentApi(
-        client,
+        TEST_CTX,
         "agent_ver_123",
         "Test Agent",
         conversationConfig,
@@ -51,27 +65,24 @@ describe("Agent versioning and branch support", () => {
         "release v1.0"
       );
 
-      expect(client.conversationalAi.agents.update).toHaveBeenCalledTimes(1);
-      const [agentId, payload] = (
-        client.conversationalAi.agents.update as jest.Mock
-      ).mock.calls[0];
-
-      expect(agentId).toBe("agent_ver_123");
-      expect(payload).toEqual(
+      expect(fetchMock).toHaveBeenCalledTimes(1);
+      const [url] = fetchMock.mock.calls[0];
+      expect(url).toBe("https://api.test/v1/convai/agents/agent_ver_123");
+      expect(sentBody(fetchMock)).toEqual(
         expect.objectContaining({
-          versionDescription: "release v1.0",
+          version_description: "release v1.0",
         })
       );
     });
 
     it("should not include versionDescription when not provided", async () => {
-      const client = makeMockClient();
+      const fetchMock = mockFetch({ agent_id: "agent_ver_123" });
       const conversationConfig = {
         agent: { prompt: { prompt: "hi", temperature: 0 } },
       } as unknown as Record<string, unknown>;
 
       await updateAgentApi(
-        client,
+        TEST_CTX,
         "agent_ver_123",
         "Test Agent",
         conversationConfig,
@@ -80,24 +91,21 @@ describe("Agent versioning and branch support", () => {
         []
       );
 
-      const [, payload] = (
-        client.conversationalAi.agents.update as jest.Mock
-      ).mock.calls[0];
-
-      expect(payload.versionDescription).toBeUndefined();
+      expect(sentBody(fetchMock)).not.toHaveProperty("version_description");
     });
 
     it("should return versionId and branchId from API response", async () => {
-      const client = makeMockClient({
-        versionId: "ver_xyz",
-        branchId: "branch_feat",
+      mockFetch({
+        agent_id: "agent_ver_123",
+        version_id: "ver_xyz",
+        branch_id: "branch_feat",
       });
       const conversationConfig = {
         agent: { prompt: { prompt: "hi", temperature: 0 } },
       } as unknown as Record<string, unknown>;
 
       const result = await updateAgentApi(
-        client,
+        TEST_CTX,
         "agent_ver_123",
         "Test Agent",
         conversationConfig,
@@ -115,18 +123,14 @@ describe("Agent versioning and branch support", () => {
     });
 
     it("should handle missing versionId/branchId in response", async () => {
-      const client = makeMockClient();
-      // Override update to return response without version fields
-      (client.conversationalAi.agents.update as jest.Mock).mockResolvedValue({
-        agentId: "agent_ver_123",
-      });
+      mockFetch({ agent_id: "agent_ver_123" });
 
       const conversationConfig = {
         agent: { prompt: { prompt: "hi", temperature: 0 } },
       } as unknown as Record<string, unknown>;
 
       const result = await updateAgentApi(
-        client,
+        TEST_CTX,
         "agent_ver_123",
         "Test Agent",
         conversationConfig
diff --git a/src/__tests__/workflow.test.ts b/src/__tests__/workflow.test.ts
index ee94d95..8af4bc8 100644
--- a/src/__tests__/workflow.test.ts
+++ b/src/__tests__/workflow.test.ts
@@ -1,6 +1,26 @@
 import { createAgentApi, updateAgentApi, getAgentApi } from "../shared/elevenlabs-api";
 import { ElevenLabsClient } from "@elevenlabs/elevenlabs-js";
 
+const TEST_CTX = { apiKey: "test-key", baseUrl: "https://api.test" };
+
+const realFetch = global.fetch;
+afterEach(() => {
+  global.fetch = realFetch;
+});
+
+function mockFetch(response: Record<string, unknown> = { agent_id: "agent_workflow_123" }): jest.Mock {
+  const fetchMock = jest.fn().mockResolvedValue({
+    ok: true,
+    json: async () => response,
+  });
+  global.fetch = fetchMock as unknown as typeof fetch;
+  return fetchMock;
+}
+
+function sentBody(fetchMock: jest.Mock): Record<string, any> {
+  return JSON.parse(fetchMock.mock.calls[0][1].body as string);
+}
+
 describe("Workflow support in agents", () => {
   function makeMockClient(includeWorkflow: boolean = false) {
     const mockWorkflow = includeWorkflow ? {
@@ -30,8 +50,6 @@ describe("Workflow support in agents", () => {
       }
     } : undefined;
 
-    const create = jest.fn().mockResolvedValue({ agentId: "agent_workflow_123" });
-    const update = jest.fn().mockResolvedValue({ agentId: "agent_workflow_123" });
     const get = jest.fn().mockResolvedValue({
       agentId: "agent_workflow_123",
       name: "Test Agent with Workflow",
@@ -55,14 +73,14 @@ describe("Workflow support in agents", () => {
 
     return {
       conversationalAi: {
-        agents: { create, update, get },
+        agents: { get },
       },
     } as unknown as ElevenLabsClient;
   }
 
   describe("createAgentApi", () => {
     it("should send workflow when provided", async () => {
-      const client = makeMockClient();
+      const fetchMock = mockFetch();
       const conversation_config = {
         conversation: {
           client_events: ["audio"],
@@ -81,7 +99,7 @@ describe("Workflow support in agents", () => {
       };
 
       await createAgentApi(
-        client,
+        TEST_CTX,
         "Agent with Workflow",
         conversation_config,
         undefined,
@@ -89,30 +107,20 @@ describe("Workflow support in agents", () => {
         ["workflow"]
       );
 
-      expect(client.conversationalAi.agents.create).toHaveBeenCalledTimes(1);
-      const payload = (client.conversationalAi.agents.create as jest.Mock).mock.calls[0][0];
+      expect(fetchMock).toHaveBeenCalledTimes(1);
+      const body = sentBody(fetchMock);
 
-      // Workflow node/edge identifier keys should be preserved (not camel-cased)
-      // Only schema fields within nodes/edges should be converted
-      expect(payload).toEqual(
+      expect(body).toEqual(
         expect.objectContaining({
           name: "Agent with Workflow",
-          workflow: expect.objectContaining({
-            nodes: expect.objectContaining({
-              start: expect.any(Object),   // "start" has no underscore, stays as-is
-              end: expect.any(Object),     // "end" has no underscore, stays as-is
-            }),
-            edges: expect.objectContaining({
-              edge_1: expect.any(Object),  // edge_1 preserved as identifier
-            }),
-          }),
+          workflow,
           tags: ["workflow"],
         })
       );
     });
 
     it("should handle undefined workflow gracefully", async () => {
-      const client = makeMockClient();
+      const fetchMock = mockFetch();
       const conversation_config = {
         conversation: {
           client_events: ["audio"],
@@ -121,7 +129,7 @@ describe("Workflow support in agents", () => {
       } as unknown as Record<string, unknown>;
 
       await createAgentApi(
-        client,
+        TEST_CTX,
         "Agent without Workflow",
         conversation_config,
         undefined,
@@ -129,21 +137,17 @@ describe("Workflow support in agents", () => {
         []
       );
 
-      expect(client.conversationalAi.agents.create).toHaveBeenCalledTimes(1);
-      const payload = (client.conversationalAi.agents.create as jest.Mock).mock.calls[0][0];
+      expect(fetchMock).toHaveBeenCalledTimes(1);
+      const body = sentBody(fetchMock);
 
-      expect(payload).toEqual(
-        expect.objectContaining({
-          name: "Agent without Workflow",
-          workflow: undefined,
-        })
-      );
+      expect(body.name).toBe("Agent without Workflow");
+      expect(body).not.toHaveProperty("workflow");
     });
   });
 
   describe("updateAgentApi", () => {
     it("should send workflow when updating an agent", async () => {
-      const client = makeMockClient();
+      const fetchMock = mockFetch();
       const conversation_config = {
         conversation: {
           client_events: ["audio"],
@@ -161,7 +165,7 @@ describe("Workflow support in agents", () => {
       };
 
       await updateAgentApi(
-        client,
+        TEST_CTX,
         "agent_workflow_123",
         "Updated Agent",
         conversation_config,
@@ -170,29 +174,22 @@ describe("Workflow support in agents", () => {
         ["updated"]
       );
 
-      expect(client.conversationalAi.agents.update).toHaveBeenCalledTimes(1);
-      const [agentId, payload] = (
-        client.conversationalAi.agents.update as jest.Mock
-      ).mock.calls[0];
+      expect(fetchMock).toHaveBeenCalledTimes(1);
+      const [url, init] = fetchMock.mock.calls[0];
+      expect(url).toBe("https://api.test/v1/convai/agents/agent_workflow_123");
+      expect(init.method).toBe("PATCH");
 
-      expect(agentId).toBe("agent_workflow_123");
-      // Workflow node/edge identifier keys should be preserved (not camel-cased)
-      expect(payload).toEqual(
+      expect(sentBody(fetchMock)).toEqual(
         expect.objectContaining({
           name: "Updated Agent",
-          workflow: expect.objectContaining({
-            nodes: expect.objectContaining({
-              updated_start: expect.any(Object),  // preserved as identifier
-              updated_end: expect.any(Object),    // preserved as identifier
-            }),
-          }),
+          workflow,
           tags: ["updated"],
         })
       );
     });
 
     it("should allow clearing workflow by passing undefined", async () => {
-      const client = makeMockClient();
+      const fetchMock = mockFetch();
       const conversation_config = {
         conversation: {
           client_events: ["audio"],
@@ -200,7 +197,7 @@ describe("Workflow support in agents", () => {
       } as unknown as Record<string, unknown>;
 
       await updateAgentApi(
-        client,
+        TEST_CTX,
         "agent_workflow_123",
         "Agent Workflow Cleared",
         conversation_config,
@@ -209,16 +206,59 @@ describe("Workflow support in agents", () => {
         []
       );
 
-      expect(client.conversationalAi.agents.update).toHaveBeenCalledTimes(1);
-      const [, payload] = (
-        client.conversationalAi.agents.update as jest.Mock
-      ).mock.calls[0];
+      expect(fetchMock).toHaveBeenCalledTimes(1);
+      expect(sentBody(fetchMock)).not.toHaveProperty("workflow");
+    });
 
-      expect(payload).toEqual(
-        expect.objectContaining({
-          workflow: undefined,
-        })
+    // Regression: workflows with expression-type edge conditions containing `llm`
+    // or `null_literal` AST nodes must round-trip through push unchanged. The
+    // SDK's generated serializers reject these (missing "value" key / unknown
+    // union member), which is why push sends raw JSON.
+    it("round-trips expression conditions with llm and null_literal nodes verbatim", async () => {
+      const fetchMock = mockFetch();
+
+      const workflow = {
+        edges: {
+          edge_01: {
+            source: "node_a",
+            target: "node_b",
+            forward_condition: {
+              type: "expression",
+              expression: {
+                type: "and_operator",
+                children: [
+                  {
+                    type: "neq_operator",
+                    left: { type: "dynamic_variable", name: "system__caller_id" },
+                    right: { type: "null_literal" }
+                  },
+                  {
+                    type: "llm",
+                    value_schema: {
+                      type: "boolean",
+                      description: "customer expressed intention to book an appointment"
+                    },
+                    prompt: "customer expressed intention to book an appointment"
+                  }
+                ]
+              }
+            }
+          }
+        },
+        nodes: {}
+      };
+
+      await updateAgentApi(
+        TEST_CTX,
+        "agent_workflow_123",
+        "Expression Agent",
+        { agent: { prompt: { prompt: "hi" } } } as unknown as Record<string, unknown>,
+        undefined,
+        workflow,
+        []
       );
+
+      expect(sentBody(fetchMock).workflow).toEqual(workflow);
     });
   });
 
@@ -269,7 +309,7 @@ describe("Workflow support in agents", () => {
 
   describe("Workflow persistence in pull/push flow", () => {
     it("should preserve complex workflow structures", async () => {
-      const client = makeMockClient();
+      const fetchMock = mockFetch();
 
       // Complex workflow with multiple node types
       const complexWorkflow = {
@@ -314,7 +354,7 @@ describe("Workflow support in agents", () => {
       };
 
       await createAgentApi(
-        client,
+        TEST_CTX,
         "Complex Workflow Agent",
         { agent: { prompt: { prompt: "test", temperature: 0 } } } as unknown as Record<string, unknown>,
         undefined,
@@ -322,21 +362,11 @@ describe("Workflow support in agents", () => {
         ["complex"]
       );
 
-      const payload = (client.conversationalAi.agents.create as jest.Mock).mock.calls[0][0];
-
-      // Workflow node/edge identifier keys should be preserved (not camel-cased)
-      expect(payload.workflow.nodes).toHaveProperty("start_1");     // preserved as identifier
-      expect(payload.workflow.nodes).toHaveProperty("agent_1");     // preserved as identifier
-      expect(payload.workflow.nodes).toHaveProperty("tool_1");      // preserved as identifier
-      expect(payload.workflow.nodes).toHaveProperty("end_1");       // preserved as identifier
-      expect(payload.workflow.edges).toHaveProperty("edge_start_to_agent");  // preserved as identifier
-      expect(payload.workflow.edges).toHaveProperty("edge_agent_to_tool");   // preserved as identifier
-      expect(payload.workflow.edges).toHaveProperty("edge_tool_to_end");     // preserved as identifier
-
-      // Verify nested schema properties ARE still converted to camelCase
-      expect(payload.workflow.nodes.start_1.config).toHaveProperty("initialMessage"); // initial_message → initialMessage
-      expect(payload.workflow.nodes.agent_1).toHaveProperty("agentId");    // agent_id → agentId
-      expect(payload.workflow.nodes.tool_1).toHaveProperty("toolId");      // tool_id → toolId
+      const body = sentBody(fetchMock);
+
+      // The pulled snake_case workflow must reach the wire unchanged: node/edge
+      // identifier keys AND schema fields (agent_id, tool_id, initial_message)
+      expect(body.workflow).toEqual(complexWorkflow);
     });
   });
 });
diff --git a/src/agents/commands/add.ts b/src/agents/commands/add.ts
index 617db98..781db50 100644
--- a/src/agents/commands/add.ts
+++ b/src/agents/commands/add.ts
@@ -6,7 +6,7 @@ import fs from 'fs-extra';
 import AddAgentView from '../ui/AddAgentView.js';
 import { readConfig, writeConfig, generateUniqueFilename } from '../../shared/utils.js';
 import { getTemplateByName, AgentConfig } from '../templates.js';
-import { getElevenLabsClient, createAgentApi } from '../../shared/elevenlabs-api.js';
+import { getApiContext, createAgentApi } from '../../shared/elevenlabs-api.js';
 
 const AGENTS_CONFIG_FILE = "agents.json";
 
@@ -111,7 +111,7 @@ export function createAddCommand(): Command {
         // Create agent in ElevenLabs first to get ID
         console.log(`Creating agent '${agentName}' in ElevenLabs...`);
 
-        const client = await getElevenLabsClient();
+        const apiCtx = await getApiContext();
 
         // Extract config components
         const conversationConfig = agentConfig.conversation_config || {};
@@ -121,7 +121,7 @@ export function createAddCommand(): Command {
 
         // Create new agent
         const agentId = await createAgentApi(
-          client,
+          apiCtx,
           agentName,
           conversationConfig,
           platformSettings,
diff --git a/src/agents/commands/push-impl.ts b/src/agents/commands/push-impl.ts
index d1c1c0f..740c1d9 100644
--- a/src/agents/commands/push-impl.ts
+++ b/src/agents/commands/push-impl.ts
@@ -1,7 +1,7 @@
 import path from 'path';
 import fs from 'fs-extra';
 import { readConfig, writeConfig } from '../../shared/utils.js';
-import { getElevenLabsClient, createAgentApi, updateAgentApi, resolveBranchId } from '../../shared/elevenlabs-api.js';
+import { getElevenLabsClient, getApiContext, createAgentApi, updateAgentApi, resolveBranchId } from '../../shared/elevenlabs-api.js';
 import { verifyAgentPush } from '../../shared/verify.js';
 import { AgentConfig } from '../templates.js';
 
@@ -92,8 +92,10 @@ export async function pushAgents(dryRun: boolean = false, agentId?: string, vers
 
     // Initialize ElevenLabs client
     let client;
+    let apiCtx;
     try {
       client = await getElevenLabsClient();
+      apiCtx = await getApiContext();
     } catch (error) {
       console.log(`Error: ${error}`);
       console.log(`Skipping agent ${agentDefName} - not configured`);
@@ -120,7 +122,7 @@ export async function pushAgents(dryRun: boolean = false, agentId?: string, vers
       if (!currentAgentId) {
         // Create new agent
         const newAgentId = await createAgentApi(
-          client,
+          apiCtx,
           agentDisplayName,
           conversationConfig,
           platformSettings,
@@ -141,7 +143,7 @@ export async function pushAgents(dryRun: boolean = false, agentId?: string, vers
       } else {
         // Update existing agent
         const result = await updateAgentApi(
-          client,
+          apiCtx,
           currentAgentId,
           agentDisplayName,
           conversationConfig,
@@ -183,7 +185,7 @@ export async function pushAgents(dryRun: boolean = false, agentId?: string, vers
 
             console.log(`  Pushing branch '${branchName}'...`);
             const branchResult = await updateAgentApi(
-              client,
+              apiCtx,
               currentAgentId,
               branchConfig.name,
               branchConversationConfig,
diff --git a/src/agents/ui/AddAgentView.tsx b/src/agents/ui/AddAgentView.tsx
index 24dcbb3..9b38f2e 100644
--- a/src/agents/ui/AddAgentView.tsx
+++ b/src/agents/ui/AddAgentView.tsx
@@ -8,7 +8,7 @@ import theme from '../../ui/themes/elevenlabs.js';
 import { getTemplateByName, getTemplateOptions } from '../templates.js';
 import { writeConfig, generateUniqueFilename } from '../../shared/utils.js';
 import { createAgentApi } from '../../shared/elevenlabs-api.js';
-import { getElevenLabsClient } from '../../shared/elevenlabs-api.js';
+import { getApiContext } from '../../shared/elevenlabs-api.js';
 import path from 'path';
 import fs from 'fs-extra';
 
@@ -68,13 +68,13 @@ export const AddAgentView: React.FC<AddAgentViewProps> = ({
       
       // Step 2: Upload to ElevenLabs first to get ID
       setStatusMessage('Creating agent in ElevenLabs...');
-      const client = await getElevenLabsClient();
+      const apiCtx = await getApiContext();
       const conversationConfig = agentConfig.conversation_config || {};
       const platformSettings = agentConfig.platform_settings;
       const workflow = agentConfig.workflow;
       const tags = agentConfig.tags || [];
       const agentId = await createAgentApi(
-        client,
+        apiCtx,
         agentName,
         conversationConfig,
         platformSettings,
diff --git a/src/agents/ui/PushView.tsx b/src/agents/ui/PushView.tsx
index 6d5e118..563c546 100644
--- a/src/agents/ui/PushView.tsx
+++ b/src/agents/ui/PushView.tsx
@@ -2,7 +2,7 @@ import React, { useState, useEffect } from 'react';
 import { Box, Text, useApp } from 'ink';
 import App from '../../ui/App.js';
 import theme from '../../ui/themes/elevenlabs.js';
-import { getElevenLabsClient, createAgentApi, updateAgentApi, resolveBranchId } from '../../shared/elevenlabs-api.js';
+import { getElevenLabsClient, getApiContext, createAgentApi, updateAgentApi, resolveBranchId } from '../../shared/elevenlabs-api.js';
 import { readConfig, writeConfig } from '../../shared/utils.js';
 import fs from 'fs-extra';
 import path from 'path';
@@ -99,6 +99,7 @@ export const PushView: React.FC<PushViewProps> = ({
 
           // Get ElevenLabs client
           const client = await getElevenLabsClient();
+          const apiCtx = await getApiContext();
 
           // Resolve branch if needed
           let branchId: string | undefined;
@@ -116,7 +117,7 @@ export const PushView: React.FC<PushViewProps> = ({
           if (!agentId) {
             // Create new agent
             const newAgentId = await createAgentApi(
-              client,
+              apiCtx,
               agentDisplayName,
               conversationConfig,
               platformSettings,
@@ -146,7 +147,7 @@ export const PushView: React.FC<PushViewProps> = ({
           } else {
             // Update existing agent
             const result = await updateAgentApi(
-              client,
+              apiCtx,
               agentId,
               agentDisplayName,
               conversationConfig,
@@ -172,7 +173,7 @@ export const PushView: React.FC<PushViewProps> = ({
                   if (!(await fs.pathExists(branchDef.config))) continue;
                   const branchConfig = await readConfig<any>(branchDef.config);
                   const branchResult = await updateAgentApi(
-                    client,
+                    apiCtx,
                     agentId,
                     branchConfig.name,
                     branchConfig.conversation_config || {},
diff --git a/src/shared/elevenlabs-api.ts b/src/shared/elevenlabs-api.ts
index 9cedd75..89af672 100644
--- a/src/shared/elevenlabs-api.ts
+++ b/src/shared/elevenlabs-api.ts
@@ -1,23 +1,8 @@
 import { ElevenLabsClient } from '@elevenlabs/elevenlabs-js';
 import { ElevenLabs } from '@elevenlabs/elevenlabs-js';
-import {
-  ConversationalConfig,
-  AgentPlatformSettingsRequestModel,
-  AgentWorkflowRequestModel
-} from '@elevenlabs/elevenlabs-js/api';
 import { getApiKey, loadConfig, Location } from './config.js';
 import { toCamelCaseKeys, toSnakeCaseKeys } from './utils.js';
 
-// Type guard for conversational config
-function isConversationalConfig(config: unknown): config is ConversationalConfig {
-  return typeof config === 'object' && config !== null;
-}
-
-// Type guard for platform settings
-function isPlatformSettings(settings: unknown): settings is AgentPlatformSettingsRequestModel {
-  return typeof settings === 'object' && settings !== null;
-}
-
 /**
  * Cleans conversation config before sending to API.
  * Removes the deprecated 'tools' field if 'tool_ids' is present to avoid API conflicts.
@@ -80,7 +65,7 @@ export async function getElevenLabsClient(): Promise<ElevenLabsClient> {
   const config = await loadConfig();
   const baseURL = getApiBaseUrl(config.residency);
   
-  return new ElevenLabsClient({ 
+  return new ElevenLabsClient({
     apiKey,
     baseUrl: baseURL,
     headers: {
@@ -89,10 +74,71 @@ export async function getElevenLabsClient(): Promise<ElevenLabsClient> {
   });
 }
 
+/**
+ * Connection details for raw Convai API requests.
+ */
+export interface ApiContext {
+  apiKey: string;
+  baseUrl: string;
+}
+
+/**
+ * Resolves the API key and base URL for raw Convai API requests.
+ *
+ * @throws {Error} If no API key is found
+ */
+export async function getApiContext(): Promise<ApiContext> {
+  const apiKey = await getApiKey();
+  if (!apiKey) {
+    throw new Error(`No API key found. Use 'elevenlabs auth login' to authenticate or set ELEVENLABS_API_KEY environment variable.`);
+  }
+
+  const config = await loadConfig();
+  return { apiKey, baseUrl: getApiBaseUrl(config.residency) };
+}
+
+/**
+ * Performs a raw JSON request against the Convai API.
+ *
+ * Agent create/update bodies deliberately bypass the SDK's generated
+ * serializers: they mirror the OpenAPI spec imperfectly for recursive union
+ * structures (e.g. workflow expression conditions with `llm` or `null_literal`
+ * nodes) and either reject or silently strip valid configs. Sending the
+ * snake_case config as-is guarantees a pulled config round-trips through push.
+ */
+async function convaiRequest(
+  ctx: ApiContext,
+  method: 'POST' | 'PATCH',
+  path: string,
+  body: Record<string, unknown>,
+  queryParams?: Record<string, string>
+): Promise<Record<string, unknown>> {
+  const query = queryParams && Object.keys(queryParams).length > 0
+    ? `?${new URLSearchParams(queryParams).toString()}`
+    : '';
+
+  const response = await fetch(`${ctx.baseUrl}${path}${query}`, {
+    method,
+    headers: {
+      'xi-api-key': ctx.apiKey,
+      'Content-Type': 'application/json',
+      'X-Source': 'agents-cli'
+    },
+    body: JSON.stringify(body)
+  });
+
+  if (!response.ok) {
+    const errorBody = await response.text();
+    throw new Error(`${method} ${path} failed (${response.status}): ${errorBody}`);
+  }
+
+  return await response.json() as Record<string, unknown>;
+}
+
 /**
  * Creates a new agent using the ElevenLabs API.
  *
- * @param client - An initialized ElevenLabs client
+ * @param ctx - API connection context from getApiContext()
  * @param name - The name of the agent
  * @param conversationConfigDict - A dictionary for ConversationalConfig
  * @param platformSettingsDict - An optional dictionary for AgentPlatformSettings
@@ -101,42 +147,37 @@ export async function getElevenLabsClient(): Promise<ElevenLabsClient> {
  * @returns Promise that resolves to the agent_id of the newly created agent
  */
 export async function createAgentApi(
-  client: ElevenLabsClient,
+  ctx: ApiContext,
   name: string,
   conversationConfigDict: Record<string, unknown>,
   platformSettingsDict?: Record<string, unknown>,
   workflow?: unknown,
   tags?: string[]
 ): Promise<string> {
-  if (!isConversationalConfig(conversationConfigDict)) {
+  if (typeof conversationConfigDict !== 'object' || conversationConfigDict === null) {
     throw new Error('Invalid conversation config provided');
   }
 
   // Clean config to remove deprecated 'tools' if 'tool_ids' exists
   const cleanedConfig = cleanConversationConfigForApi(conversationConfigDict);
 
-  // Normalize to camelCase for API
-  const convConfig = toCamelCaseKeys(cleanedConfig) as ConversationalConfig;
-  const platformSettings = platformSettingsDict && isPlatformSettings(platformSettingsDict) ? toCamelCaseKeys(platformSettingsDict) as AgentPlatformSettingsRequestModel : undefined;
-
-  // Normalize workflow to camelCase for API (same as conversationConfig and platformSettings)
-  const workflowConfig = workflow ? toCamelCaseKeys(workflow) as AgentWorkflowRequestModel : undefined;
-
-  const response = await client.conversationalAi.agents.create({
+  const body: Record<string, unknown> = {
     name,
-    conversationConfig: convConfig,
-    platformSettings,
-    workflow: workflowConfig,
-    tags
-  });
+    conversation_config: toSnakeCaseKeys(cleanedConfig)
+  };
+  if (platformSettingsDict) body.platform_settings = toSnakeCaseKeys(platformSettingsDict);
+  if (workflow) body.workflow = toSnakeCaseKeys(workflow);
+  if (tags) body.tags = tags;
+
+  const response = await convaiRequest(ctx, 'POST', '/v1/convai/agents/create', body);
 
-  return response.agentId;
+  return response.agent_id as string;
 }
 
 /**
  * Updates an existing agent using the ElevenLabs API.
  *
- * @param client - An initialized ElevenLabs client
+ * @param ctx - API connection context from getApiContext()
  * @param agentId - The ID of the agent to update
  * @param name - Optional new name for the agent
  * @param conversationConfigDict - Optional new dictionary for ConversationalConfig
@@ -146,7 +187,7 @@ export async function createAgentApi(
  * @returns Promise that resolves to the agent_id of the updated agent
  */
 export async function updateAgentApi(
-  client: ElevenLabsClient,
+  ctx: ApiContext,
   agentId: string,
   name?: string,
   conversationConfigDict?: Record<string, unknown>,
@@ -159,25 +200,26 @@ export async function updateAgentApi(
   // Clean config to remove deprecated 'tools' if 'tool_ids' exists
   const cleanedConfig = conversationConfigDict ? cleanConversationConfigForApi(conversationConfigDict) : undefined;
 
-  const convConfig = cleanedConfig && isConversationalConfig(cleanedConfig) ? toCamelCaseKeys(cleanedConfig) as ConversationalConfig : undefined;
-  const platformSettings = platformSettingsDict && isPlatformSettings(platformSettingsDict) ? toCamelCaseKeys(platformSettingsDict) as AgentPlatformSettingsRequestModel : undefined;
-  // Normalize workflow to camelCase for API (same as conversationConfig and platformSettings)
-  const workflowConfig = workflow ? toCamelCaseKeys(workflow) as AgentWorkflowRequestModel : undefined;
-
-  const response = await client.conversationalAi.agents.update(agentId, {
-    name,
-    conversationConfig: convConfig,
-    platformSettings,
-    workflow: workflowConfig,
-    tags,
-    versionDescription,
-    ...(branchId ? { branchId } : {})
-  });
+  const body: Record<string, unknown> = {};
+  if (name !== undefined) body.name = name;
+  if (cleanedConfig) body.conversation_config = toSnakeCaseKeys(cleanedConfig);
+  if (platformSettingsDict) body.platform_settings = toSnakeCaseKeys(platformSettingsDict);
+  if (workflow) body.workflow = toSnakeCaseKeys(workflow);
+  if (tags) body.tags = tags;
+  if (versionDescription !== undefined) body.version_description = versionDescription;
+
+  const response = await convaiRequest(
+    ctx,
+    'PATCH',
+    `/v1/convai/agents/${agentId}`,
+    body,
+    branchId ? { branch_id: branchId } : undefined
+  );
 
   return {
-    agentId: response.agentId,
-    versionId: response.versionId,
-    branchId: response.branchId
+    agentId: response.agent_id as string,
+    versionId: response.version_id as string | undefined,
+    branchId: response.branch_id as string | undefined
   };
 }