Prep v0.6.0 (#96)

This part of ACP is not yet stabilized, so marking as Draft for now

---------

Co-authored-by: Ben Brandt <benjamin.j.brandt@gmail.com>
Co-authored-by: Smit Barmase <heysmitbarmase@gmail.com>

CHANGELOG.md

@@ -1,5 +1,28 @@
 # Changelog
 
+## 0.6.0
+
+- Provide a model selector. We use the "default" model by default, and the user can change it via the client.
+- Make sure writes require permissions when necessary: https://github.com/zed-industries/claude-code-acp/pull/92
+- Add support for appending or overriding the system prompt: https://github.com/zed-industries/claude-code-acp/pull/91
+- Update to @anthropic-ai/claude-agent-sdk@v0.1.15
+- Update to @agentclientprotocol/sdk@0.4.8
+
+## 0.5.5
+
+- Migrate to @agentclientprotocol/sdk@0.4.5
+- Update to @anthropic-ai/claude-agent-sdk@v0.1.13
+
+## 0.5.4
+
+- Update to @anthropic-ai/claude-agent-sdk@v0.1.11
+- Enable setting CLAUDE_CODE_EXECUTABLE to override the executable used by the SDK https://github.com/zed-industries/claude-code-acp/pull/86
+
+## 0.5.3
+
+- Update to @anthropic-ai/claude-agent-sdk@v0.1.8
+- Update to @zed-industries/agent-client-protocol@v0.4.5
+
 ## 0.5.2
 
 - Add back @anthropic-ai/claude-code@2.0.1 as runtime dependency

package.json

@@ -6,7 +6,7 @@
   "bin": {
     "claude-code-acp": "./dist/index.js"
   },
-  "version": "0.5.2",
+  "version": "0.6.0",
   "description": "An ACP-compatible coding agent powered by the Claude Code SDK (TypeScript)",
   "main": "dist/index.js",
   "type": "module",
@@ -51,10 +51,10 @@
   "author": "Zed Industries",
   "license": "Apache-2.0",
   "dependencies": {
-    "@anthropic-ai/claude-agent-sdk": "0.1.1",
-    "@anthropic-ai/claude-code": "2.0.1",
-    "@modelcontextprotocol/sdk": "1.18.2",
-    "@zed-industries/agent-client-protocol": "0.4.3",
+    "@agentclientprotocol/sdk": "0.4.8",
+    "@anthropic-ai/claude-agent-sdk": "0.1.15",
+    "@anthropic-ai/claude-code": "2.0.15",
+    "@modelcontextprotocol/sdk": "1.20.0",
     "diff": "8.0.2",
     "express": "5.1.0",
     "minimist": "1.2.8",
@@ -64,17 +64,17 @@
     "@anthropic-ai/sdk": "^0.65.0",
     "@types/express": "5.0.3",
     "@types/minimist": "1.2.5",
-    "@types/node": "24.6.0",
+    "@types/node": "24.7.2",
     "@types/uuid": "10.0.0",
-    "@typescript-eslint/eslint-plugin": "8.45.0",
-    "@typescript-eslint/parser": "8.45.0",
+    "@typescript-eslint/eslint-plugin": "8.46.1",
+    "@typescript-eslint/parser": "8.46.1",
     "@vitest/ui": "3.2.4",
-    "eslint": "9.36.0",
+    "eslint": "9.37.0",
     "eslint-config-prettier": "10.1.8",
     "globals": "16.4.0",
     "prettier": "3.6.2",
     "ts-node": "10.9.2",
-    "typescript": "5.9.2",
+    "typescript": "5.9.3",
     "vitest": "3.2.4"
   }
 }

src/acp-agent.ts

@@ -15,13 +15,16 @@ import {
   ReadTextFileRequest,
   ReadTextFileResponse,
   RequestError,
+  SessionModelState,
+  SetSessionModelRequest,
+  SetSessionModelResponse,
   SetSessionModeRequest,
   SetSessionModeResponse,
   TerminalHandle,
   TerminalOutputResponse,
   WriteTextFileRequest,
   WriteTextFileResponse,
-} from "@zed-industries/agent-client-protocol";
+} from "@agentclientprotocol/sdk";
 import {
   McpServerConfig,
   Options,
@@ -37,7 +40,7 @@ import * as path from "node:path";
 import * as os from "node:os";
 import { v7 as uuidv7 } from "uuid";
 import { nodeToWebReadable, nodeToWebWritable, Pushable, unreachable } from "./utils.js";
-import { SessionNotification } from "@zed-industries/agent-client-protocol";
+import { SessionNotification } from "@agentclientprotocol/sdk";
 import {
   createMcpServer,
   createPermissionMcpServer,
@@ -74,6 +77,8 @@ type ToolUseCache = {
   [key: string]: { type: "tool_use"; id: string; name: string; input: any };
 };
 
+const DEFAULT_MODEL_ID = "default";
+
 // Implement the ACP Agent interface
 export class ClaudeAcpAgent implements Agent {
   sessions: {
@@ -169,16 +174,33 @@ export class ClaudeAcpAgent implements Agent {
       },
     };
 
+    let systemPrompt: Options["systemPrompt"] = { type: "preset", preset: "claude_code" };
+    if (params._meta?.systemPrompt) {
+      const customPrompt = params._meta.systemPrompt;
+      if (typeof customPrompt === "string") {
+        systemPrompt = customPrompt;
+      } else if (
+        typeof customPrompt === "object" &&
+        "append" in customPrompt &&
+        typeof customPrompt.append === "string"
+      ) {
+        systemPrompt.append = customPrompt.append;
+      }
+    }
+
     const options: Options = {
       cwd: params.cwd,
       mcpServers,
-      systemPrompt: { type: "preset", preset: "claude_code" },
+      systemPrompt,
       settingSources: ["user", "project", "local"],
       permissionPromptToolName: PERMISSION_TOOL_NAME,
       stderr: (err) => console.error(err),
       // note: although not documented by the types, passing an absolute path
       // here works to find zed's managed node version.
       executable: process.execPath as any,
+      ...(process.env.CLAUDE_CODE_EXECUTABLE && {
+        pathToClaudeCodeExecutable: process.env.CLAUDE_CODE_EXECUTABLE,
+      }),
     };
 
     const allowedTools = [];
@@ -188,7 +210,6 @@ export class ClaudeAcpAgent implements Agent {
       disallowedTools.push("Read");
     }
     if (this.clientCapabilities?.fs?.writeTextFile) {
-      allowedTools.push(toolNames.write);
       disallowedTools.push("Write", "Edit");
     }
     if (this.clientCapabilities?.terminal) {
@@ -224,8 +245,11 @@ export class ClaudeAcpAgent implements Agent {
       });
     });
 
+    const models = await getAvailableModels(q);
+
     return {
       sessionId,
+      models,
       modes: {
         currentModeId: "default",
         availableModes: [
@@ -372,6 +396,13 @@ export class ClaudeAcpAgent implements Agent {
     await this.sessions[params.sessionId].query.interrupt();
   }
 
+  async setSessionModel(params: SetSessionModelRequest): Promise<SetSessionModelResponse | void> {
+    if (!this.sessions[params.sessionId]) {
+      throw new Error("Session not found");
+    }
+    await this.sessions[params.sessionId].query.setModel(params.modelId);
+  }
+
   async setSessionMode(params: SetSessionModeRequest): Promise<SetSessionModeResponse> {
     if (!this.sessions[params.sessionId]) {
       throw new Error("Session not found");
@@ -383,10 +414,17 @@ export class ClaudeAcpAgent implements Agent {
       case "bypassPermissions":
       case "plan":
         this.sessions[params.sessionId].permissionMode = params.modeId;
-        await this.sessions[params.sessionId].query.setPermissionMode(params.modeId);
+        try {
+          await this.sessions[params.sessionId].query.setPermissionMode(params.modeId);
+        } catch (error) {
+          const errorMessage =
+            error instanceof Error && error.message ? error.message : "Invalid Mode";
+
+          throw new Error(errorMessage);
+        }
         return {};
       default:
-        throw new Error("Invalid mode");
+        throw new Error("Invalid Mode");
     }
   }
 
@@ -405,6 +443,26 @@ export class ClaudeAcpAgent implements Agent {
   }
 }
 
+async function getAvailableModels(query: Query): Promise<SessionModelState> {
+  const models = await query.supportedModels();
+
+  // Query doesn't give us access to the currently selected model, so we default to "default" if it is there,
+  // otherwise we just choose the first model in the list.
+  const currentModel = models.find((model) => model.value === DEFAULT_MODEL_ID) || models[0];
+  await query.setModel(currentModel.value);
+
+  const availableModels = models.map((model) => ({
+    modelId: model.value,
+    name: model.displayName,
+    description: model.description,
+  }));
+
+  return {
+    availableModels,
+    currentModelId: currentModel.value,
+  };
+}
+
 async function getAvailableSlashCommands(query: Query): Promise<AvailableCommand[]> {
   const UNSUPPORTED_COMMANDS = [
     "add-dir",

src/mcp-server.ts

@@ -5,7 +5,7 @@ import { StreamableHTTPServerTransport } from "@modelcontextprotocol/sdk/server/
 import { z } from "zod";
 import { Server } from "node:http";
 import { ClaudeAcpAgent } from "./acp-agent.js";
-import { ClientCapabilities, TerminalOutputResponse } from "@zed-industries/agent-client-protocol";
+import { ClientCapabilities, TerminalOutputResponse } from "@agentclientprotocol/sdk";
 import * as diff from "diff";
 
 import { sleep, unreachable, extractLinesWithByteLimit } from "./utils.js";

src/tests/acp-agent.test.ts

@@ -14,11 +14,11 @@ import {
   SessionNotification,
   WriteTextFileRequest,
   WriteTextFileResponse,
-} from "@zed-industries/agent-client-protocol";
+} from "@agentclientprotocol/sdk";
 import { nodeToWebWritable, nodeToWebReadable } from "../utils.js";
 import { markdownEscape, toolInfoFromToolUse, toolUpdateFromToolResult } from "../tools.js";
 import { toAcpNotifications } from "../acp-agent.js";
-import { SDKAssistantMessage } from "@anthropic-ai/claude-agent-sdk";
+import { query, SDKAssistantMessage } from "@anthropic-ai/claude-agent-sdk";
 
 describe.skipIf(!process.env.RUN_INTEGRATION_TESTS)("ACP subprocess integration", () => {
   let child: ReturnType<typeof spawn>;
@@ -780,3 +780,12 @@ describe("escape markdown", () => {
     expect(escaped).toEqual("````\nfor example:\n```markdown\nHello *world*!\n```\n````");
   });
 });
+
+describe("SDK behavior", () => {
+  it("query has a 'default' model", async () => {
+    const q = query({ prompt: "hi" });
+    const models = await q.supportedModels();
+    const defaultModel = models.find((m) => m.value === "default");
+    expect(defaultModel).toBeDefined();
+  });
+});

src/tools.ts

@@ -1,9 +1,4 @@
-import {
-  PlanEntry,
-  ToolCallContent,
-  ToolCallLocation,
-  ToolKind,
-} from "@zed-industries/agent-client-protocol";
+import { PlanEntry, ToolCallContent, ToolCallLocation, ToolKind } from "@agentclientprotocol/sdk";
 import { replaceAndCalculateLocation, SYSTEM_REMINDER, toolNames } from "./mcp-server.js";
 import { ToolResultBlockParam } from "@anthropic-ai/sdk/resources";