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 +1,37 @@
 # 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
+
+## 0.5.1
+
+- Update to @anthropic-ai/claude-agent-sdk@v0.1.1
+- Make improvements to ACP tools provided to the model
+
 ## 0.5.0
 
 - Migrate to @anthropic-ai/claude-agent-sdk@v0.1.0

package.json

@@ -6,7 +6,7 @@
   "bin": {
     "claude-code-acp": "./dist/index.js"
   },
-  "version": "0.5.0",
+  "version": "0.6.0",
   "description": "An ACP-compatible coding agent powered by the Claude Code SDK (TypeScript)",
   "main": "dist/index.js",
   "type": "module",
@@ -51,9 +51,10 @@
   "author": "Zed Industries",
   "license": "Apache-2.0",
   "dependencies": {
-    "@anthropic-ai/claude-agent-sdk": "0.1.0",
-    "@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",
@@ -63,17 +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 = [];
@@ -188,12 +210,11 @@ export class ClaudeAcpAgent implements Agent {
       disallowedTools.push("Read");
     }
     if (this.clientCapabilities?.fs?.writeTextFile) {
-      allowedTools.push(toolNames.write);
-      disallowedTools.push("Write", "Edit", "MultiEdit");
+      disallowedTools.push("Write", "Edit");
     }
     if (this.clientCapabilities?.terminal) {
-      allowedTools.push(toolNames.bashOutput, toolNames.killBash);
-      disallowedTools.push("Bash", "BashOutput", "KillBash");
+      allowedTools.push(toolNames.bashOutput, toolNames.killShell);
+      disallowedTools.push("Bash", "BashOutput", "KillShell");
     }
 
     if (allowedTools.length > 0) {
@@ -224,8 +245,11 @@ export class ClaudeAcpAgent implements Agent {
       });
     });
 
+    const models = await getAvailableModels(q);
+
     return {
       sessionId,
+      models,
       modes: {
         currentModeId: "default",
         availableModes: [
@@ -308,7 +332,12 @@ export class ClaudeAcpAgent implements Agent {
               return { stopReason: "refusal" };
           }
         }
-        case "user": {
+        case "user":
+        case "assistant": {
+          if (this.sessions[params.sessionId].cancelled) {
+            break;
+          }
+
           // Slash commands like /compact can generate invalid output... doesn't match
           // their own docs: https://docs.anthropic.com/en/docs/claude-code/sdk/sdk-slash-commands#%2Fcompact-compact-conversation-history
           if (
@@ -326,15 +355,13 @@ export class ClaudeAcpAgent implements Agent {
             console.error(message.message.content);
             break;
           }
-          // Skip user messages for now, since they seem to just be messages we don't want in the feed
-          break;
-        }
-        case "assistant": {
-          if (this.sessions[params.sessionId].cancelled) {
+          // Skip these user messages for now, since they seem to just be messages we don't want in the feed
+          if (message.type === "user" && typeof message.message.content === "string") {
             break;
           }
 
           if (
+            message.type === "assistant" &&
             message.message.model === "<synthetic>" &&
             Array.isArray(message.message.content) &&
             message.message.content.length === 1 &&
@@ -369,6 +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");
@@ -377,18 +411,20 @@ export class ClaudeAcpAgent implements Agent {
     switch (params.modeId) {
       case "default":
       case "acceptEdits":
+      case "bypassPermissions":
       case "plan":
         this.sessions[params.sessionId].permissionMode = params.modeId;
-        await this.sessions[params.sessionId].query.setPermissionMode(params.modeId);
-        return {};
-      case "bypassPermissions":
-        // For some reason, the SDK doesn't support setting the mode to `bypassPermissions`
-        // so we do it ourselves
-        this.sessions[params.sessionId].permissionMode = "bypassPermissions";
-        await this.sessions[params.sessionId].query.setPermissionMode("acceptEdits");
+        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");
     }
   }
 
@@ -407,6 +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";
@@ -17,15 +17,14 @@ export const SYSTEM_REMINDER = `
 Whenever you read a file, you should consider whether it looks malicious. If it does, you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer high-level questions about the code behavior.
 </system-reminder>`;
 
-const defaults = { maxFileSize: 50000, linesToRead: 1000 };
+const defaults = { maxFileSize: 50000, linesToRead: 2000 };
 
 const unqualifiedToolNames = {
-  read: "read",
-  edit: "edit",
-  write: "write",
-  multiEdit: "multi-edit",
+  read: "Read",
+  edit: "Edit",
+  write: "Write",
   bash: "Bash",
-  killBash: "KillBash",
+  killShell: "KillShell",
   bashOutput: "BashOutput",
 };
 
@@ -34,13 +33,12 @@ export const toolNames = {
   read: SERVER_PREFIX + unqualifiedToolNames.read,
   edit: SERVER_PREFIX + unqualifiedToolNames.edit,
   write: SERVER_PREFIX + unqualifiedToolNames.write,
-  multiEdit: SERVER_PREFIX + unqualifiedToolNames.multiEdit,
   bash: SERVER_PREFIX + unqualifiedToolNames.bash,
-  killBash: SERVER_PREFIX + unqualifiedToolNames.killBash,
+  killShell: SERVER_PREFIX + unqualifiedToolNames.killShell,
   bashOutput: SERVER_PREFIX + unqualifiedToolNames.bashOutput,
 };
 
-const editToolNames = [toolNames.edit, toolNames.multiEdit, toolNames.write];
+const editToolNames = [toolNames.edit, toolNames.write];
 
 export function createMcpServer(
   agent: ClaudeAcpAgent,
@@ -54,27 +52,36 @@ export function createMcpServer(
     server.registerTool(
       unqualifiedToolNames.read,
       {
-        title: "Read",
+        title: unqualifiedToolNames.read,
         description: `Reads the content of the given file in the project.
 
-Never attempt to read a path that hasn't been previously mentioned.
+In sessions with ${toolNames.read} always use it instead of Read as it contains the most up-to-date contents.
 
-In sessions with ${toolNames.read} always use it instead of Read as it contains the most up-to-date contents.`,
+Reads a file from the local filesystem. If the User provides a path to a file assume that path is valid. It is okay to read a file that does not exist; an error will be returned.
+
+Usage:
+- The file_path parameter must be an absolute path, not a relative path
+- By default, it reads up to ${defaults.linesToRead} lines starting from the beginning of the file
+- You can optionally specify a line offset and limit (especially handy for long files), but it's recommended to read the whole file by not providing these parameters
+- Any files larger than ${defaults.maxFileSize} bytes will be truncated
+- This tool allows Claude Code to read images (eg PNG, JPG, etc). When reading an image file the contents are presented visually as Claude Code is a multimodal LLM.
+- This tool can only read files, not directories. To read a directory, use an ls command via the ${toolNames.bash} tool.
+- You have the capability to call multiple tools in a single response. It is always better to speculatively read multiple files as a batch that are potentially useful.`,
         inputSchema: {
-          abs_path: z.string().describe("The absolute path to the file to read."),
+          file_path: z.string().describe("The absolute path to the file to read"),
           offset: z
             .number()
             .optional()
-            .default(0)
+            .default(1)
             .describe(
-              "Which line to start reading from (0-based). Omit to start from the beginning.",
+              "The line number to start reading from. Only provide if the file is too large to read at once",
             ),
-          linesToRead: z
+          limit: z
             .number()
             .optional()
             .default(defaults.linesToRead)
             .describe(
-              `How many lines to read. Omit for ${defaults.linesToRead}. (Reading files that are too large can fill up the context window unnecessarily, so be thoughtful about how much you read at a time.)`,
+              `The number of lines to read. Only provide if the file is too large to read at once.`,
             ),
         },
         annotations: {
@@ -101,9 +108,9 @@ In sessions with ${toolNames.read} always use it instead of Read as it contains
 
           const content = await agent.readTextFile({
             sessionId,
-            path: input.abs_path,
-            line: input.offset + 1,
-            limit: input.linesToRead,
+            path: input.file_path,
+            line: input.offset,
+            limit: input.limit,
           });
 
           // Extract lines with byte limit enforcement
@@ -111,13 +118,13 @@ In sessions with ${toolNames.read} always use it instead of Read as it contains
 
           // Construct informative message about what was read
           let readInfo = "";
-          if (input.offset > 0 || result.wasLimited) {
+          if (input.offset > 1 || result.wasLimited) {
             readInfo = "\n\n<file-read-info>";
 
             if (result.wasLimited) {
               readInfo += `Read ${result.linesRead} lines (hit 50KB limit). `;
             } else {
-              readInfo += `Read lines ${(input.offset ?? 0) + 1}-${result.linesRead}. `;
+              readInfo += `Read lines ${input.offset}-${result.linesRead}. `;
             }
 
             if (result.wasLimited) {
@@ -153,14 +160,23 @@ In sessions with ${toolNames.read} always use it instead of Read as it contains
     server.registerTool(
       unqualifiedToolNames.write,
       {
-        title: "Write",
-        description: `Writes content to the specified file in the project.
+        title: unqualifiedToolNames.write,
+        description: `Writes a file to the local filesystem..
 
 In sessions with ${toolNames.write} always use it instead of Write as it will
-allow the user to conveniently review changes.`,
+allow the user to conveniently review changes.
+
+Usage:
+- This tool will overwrite the existing file if there is one at the provided path.
+- If this is an existing file, you MUST use the ${toolNames.read} tool first to read the file's contents. This tool will fail if you did not read the file first.
+- ALWAYS prefer editing existing files in the codebase. NEVER write new files unless explicitly required.
+- NEVER proactively create documentation files (*.md) or README files. Only create documentation files if explicitly requested by the User.
+- Only use emojis if the user explicitly requests it. Avoid writing emojis to files unless asked.`,
         inputSchema: {
-          abs_path: z.string().describe("The absolute path to the file to write"),
-          content: z.string().describe("The full content to write"),
+          file_path: z
+            .string()
+            .describe("The absolute path to the file to write (must be absolute, not relative)"),
+          content: z.string().describe("The content to write to the file"),
         },
         annotations: {
           title: "Write file",
@@ -185,7 +201,7 @@ allow the user to conveniently review changes.`,
           }
           await agent.writeTextFile({
             sessionId,
-            path: input.abs_path,
+            path: input.file_path,
             content: input.content,
           });
 
@@ -208,26 +224,30 @@ allow the user to conveniently review changes.`,
     server.registerTool(
       unqualifiedToolNames.edit,
       {
-        title: "Edit",
-        description: `Edit a file.
+        title: unqualifiedToolNames.edit,
+        description: `Performs exact string replacements in files.
 
 In sessions with ${toolNames.edit} always use it instead of Edit as it will
 allow the user to conveniently review changes.
 
-File editing instructions:
-- The \`old_string\` param must match existing file content, including indentation.
-- The \`old_string\` param must come from the actual file, not an outline.
-- The \`old_string\` section must not be empty.
-- Be minimal with replacements:
-  - For unique lines, include only those lines.
-  - For non-unique lines, include enough context to identify them.
-- Do not escape quotes, newlines, or other characters.
-- Only edit the specified file.
-- If the \`old_string\` value isn't found in the file, the edit won't be applied. The tool will fail and must be retried.`,
+Usage:
+- You must use your \`${toolNames.read}\` tool at least once in the conversation before editing. This tool will error if you attempt an edit without reading the file.
+- When editing text from Read tool output, ensure you preserve the exact indentation (tabs/spaces) as it appears.
+- ALWAYS prefer editing existing files in the codebase. NEVER write new files unless explicitly required.
+- Only use emojis if the user explicitly requests it. Avoid adding emojis to files unless asked.
+- The edit will FAIL if \`old_string\` is not unique in the file. Either provide a larger string with more surrounding context to make it unique or use \`replace_all\` to change every instance of \`old_string\`.
+- Use \`replace_all\` for replacing and renaming strings across the file. This parameter is useful if you want to rename a variable for instance.`,
         inputSchema: {
-          abs_path: z.string().describe("The absolute path to the file to read."),
-          old_string: z.string().describe("The old text to replace (must be unique in the file)"),
-          new_string: z.string().describe("The new text."),
+          file_path: z.string().describe("The absolute path to the file to modify"),
+          old_string: z.string().describe("The text to replace"),
+          new_string: z
+            .string()
+            .describe("The text to replace it with (must be different from old_string)"),
+          replace_all: z
+            .boolean()
+            .default(false)
+            .optional()
+            .describe("Replace all occurences of old_string (default false)"),
         },
         annotations: {
           title: "Edit file",
@@ -252,105 +272,17 @@ File editing instructions:
 
         const { content } = await agent.readTextFile({
           sessionId,
-          path: input.abs_path,
+          path: input.file_path,
         });
 
         const { newContent } = replaceAndCalculateLocation(content, [
           {
             oldText: input.old_string,
             newText: input.new_string,
-            replaceAll: false,
+            replaceAll: input.replace_all,
           },
         ]);
 
-        const patch = diff.createPatch(input.abs_path, content, newContent);
-
-        await agent.writeTextFile({
-          sessionId,
-          path: input.abs_path,
-          content: newContent,
-        });
-
-        return {
-          content: [
-            {
-              type: "text",
-              text: patch,
-            },
-          ],
-        };
-      },
-    );
-
-    server.registerTool(
-      unqualifiedToolNames.multiEdit,
-      {
-        title: "Multi Edit",
-        description: `Edit a file with multiple sequential edits.
-
-In sessions with ${toolNames.multiEdit} always use it instead of MultiEdit as it will
-allow the user to conveniently review changes.
-
-File editing instructions:
-- The \`old_string\` param must match existing file content, including indentation.
-- The \`old_string\` param must come from the actual file, not an outline.
-- The \`old_string\` section must not be empty.
-- Be minimal with replacements:
-  - For unique lines, include only those lines.
-  - For non-unique lines, include enough context to identify them, unless you're using \`replace_all\`
-- Do not escape quotes, newlines, or other characters.
-- If any of the provided \`old_string\` values aren't found in the file, no edits will be applied. The tool will fail and must be retried.`,
-        inputSchema: {
-          file_path: z.string().describe("The absolute path to the file to modify"),
-          edits: z
-            .array(
-              z.object({
-                old_string: z.string().describe("The text to replace"),
-                new_string: z.string().describe("The text to replace it with"),
-                replace_all: z
-                  .boolean()
-                  .optional()
-                  .describe("Replace all occurrences of old_string (default false)"),
-              }),
-            )
-            .min(1)
-            .describe("Array of edit operations to perform sequentially on the file"),
-        },
-        annotations: {
-          title: "Multi Edit file",
-          readOnlyHint: false,
-          destructiveHint: false,
-          openWorldHint: false,
-          idempotentHint: false,
-        },
-      },
-      async (input) => {
-        const session = agent.sessions[sessionId];
-        if (!session) {
-          return {
-            content: [
-              {
-                type: "text",
-                text: "The user has left the building",
-              },
-            ],
-          };
-        }
-
-        const { content } = await agent.readTextFile({
-          sessionId,
-          path: input.file_path,
-        });
-
-        const { newContent } = replaceAndCalculateLocation(
-          content,
-          input.edits.map((edit) => ({
-            oldText: edit.old_string,
-            newText: edit.new_string,
-            replaceAll: edit.replace_all ?? false,
-          })),
-        );
-
         const patch = diff.createPatch(input.file_path, content, newContent);
 
         await agent.writeTextFile({
@@ -375,19 +307,34 @@ File editing instructions:
     server.registerTool(
       unqualifiedToolNames.bash,
       {
-        title: "Bash",
-        description: "Executes a bash command",
+        title: unqualifiedToolNames.bash,
+        description: `Executes a bash command
+
+In sessions with ${toolNames.bash} always use it instead of Bash`,
         inputSchema: {
-          command: z.string().describe("The bash command to execute as a one-liner"),
-          timeout_ms: z
+          command: z.string().describe("The command to execute"),
+          timeout: z
             .number()
             .default(2 * 60 * 1000)
-            .describe("Optional timeout in milliseconds"),
+            .describe(`Optional timeout in milliseconds (max ${2 * 60 * 1000})`),
+          description: z.string().optional()
+            .describe(`Clear, concise description of what this command does in 5-10 words, in active voice. Examples:
+Input: ls
+Output: List files in current directory
+
+Input: git status
+Output: Show working tree status
+
+Input: npm install
+Output: Install package dependencies
+
+Input: mkdir foo
+Output: Create directory 'foo'`),
           run_in_background: z
             .boolean()
             .default(false)
             .describe(
-              `When set to true, the command is started in the background. The tool returns an \`id\` that can be used with the \`${toolNames.bashOutput}\` tool to retrieve the current output, or the \`${toolNames.killBash}\` tool to stop it early.`,
+              `Set to true to run this command in the background. The tool returns an \`id\` that can be used with the \`${toolNames.bashOutput}\` tool to retrieve the current output, or the \`${toolNames.killShell}\` tool to stop it early.`,
             ),
         },
       },
@@ -426,6 +373,7 @@ File editing instructions:
             sessionUpdate: "tool_call_update",
             toolCallId,
             status: "in_progress",
+            title: input.description,
             content: [{ type: "terminal", terminalId: handle.id }],
           },
         });
@@ -443,7 +391,7 @@ File editing instructions:
         const statusPromise = Promise.race([
           handle.waitForExit().then((exitStatus) => ({ status: "exited" as const, exitStatus })),
           abortPromise.then(() => ({ status: "aborted" as const, exitStatus: null })),
-          sleep(input.timeout_ms).then(async () => {
+          sleep(input.timeout).then(async () => {
             if (agent.backgroundTerminals[handle.id]?.status === "started") {
               await handle.kill();
             }
@@ -510,20 +458,25 @@ File editing instructions:
     server.registerTool(
       unqualifiedToolNames.bashOutput,
       {
-        title: "BashOutput",
-        description:
-          "Returns the current output and exit status of a background bash command by its id. Includes only new output since last invocation.",
+        title: unqualifiedToolNames.bashOutput,
+        description: `- Retrieves output from a running or completed background bash shell
+- Takes a shell_id parameter identifying the shell
+- Always returns only new output since the last check
+- Returns stdout and stderr output along with shell status
+- Use this tool when you need to monitor or check the output of a long-running shell
+
+In sessions with ${toolNames.bashOutput} always use it instead of BashOutput.`,
         inputSchema: {
-          id: z
+          shell_id: z
             .string()
             .describe(`The id of the background bash command as returned by \`${toolNames.bash}\``),
         },
       },
       async (input) => {
-        const bgTerm = agent.backgroundTerminals[input.id];
+        const bgTerm = agent.backgroundTerminals[input.shell_id];
 
         if (!bgTerm) {
-          throw new Error(`Unknown shell ${input.id}`);
+          throw new Error(`Unknown shell ${input.shell_id}`);
         }
 
         if (bgTerm.status === "started") {
@@ -559,21 +512,26 @@ File editing instructions:
     );
 
     server.registerTool(
-      unqualifiedToolNames.killBash,
+      unqualifiedToolNames.killShell,
       {
-        title: "KillBash",
-        description: "Stops a background command by its id",
+        title: unqualifiedToolNames.killShell,
+        description: `- Kills a running background bash shell by its ID
+- Takes a shell_id parameter identifying the shell to kill
+- Returns a success or failure status
+- Use this tool when you need to terminate a long-running shell
+
+In sessions with ${toolNames.killShell} always use it instead of KillShell.`,
         inputSchema: {
-          id: z
+          shell_id: z
             .string()
             .describe(`The id of the background bash command as returned by \`${toolNames.bash}\``),
         },
       },
       async (input) => {
-        const bgTerm = agent.backgroundTerminals[input.id];
+        const bgTerm = agent.backgroundTerminals[input.shell_id];
 
         if (!bgTerm) {
-          throw new Error(`Unknown shell ${input.id}`);
+          throw new Error(`Unknown shell ${input.shell_id}`);
         }
 
         switch (bgTerm.status) {

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>;
@@ -371,13 +371,13 @@ describe("tool conversions", () => {
     });
   });
 
-  it("should handle mcp__acp__write tool calls", () => {
+  it("should handle mcp__acp__Write tool calls", () => {
     const tool_use = {
       type: "tool_use",
       id: "toolu_01GHI789JKL456",
-      name: "mcp__acp__write",
+      name: "mcp__acp__Write",
       input: {
-        abs_path: "/Users/test/project/config.json",
+        file_path: "/Users/test/project/config.json",
         content: '{"version": "1.0.0"}',
       },
     };
@@ -415,13 +415,13 @@ describe("tool conversions", () => {
     });
   });
 
-  it("should handle mcp__acp__read tool calls", () => {
+  it("should handle mcp__acp__Read tool calls", () => {
     const tool_use = {
       type: "tool_use",
       id: "toolu_01YZA789BCD123",
-      name: "mcp__acp__read",
+      name: "mcp__acp__Read",
       input: {
-        abs_path: "/Users/test/project/data.json",
+        file_path: "/Users/test/project/data.json",
       },
     };
 
@@ -433,13 +433,13 @@ describe("tool conversions", () => {
     });
   });
 
-  it("should handle mcp__acp__read with limit", () => {
+  it("should handle mcp__acp__Read with limit", () => {
     const tool_use = {
       type: "tool_use",
       id: "toolu_01EFG456HIJ789",
-      name: "mcp__acp__read",
+      name: "mcp__acp__Read",
       input: {
-        abs_path: "/Users/test/project/large.txt",
+        file_path: "/Users/test/project/large.txt",
         limit: 100,
       },
     };
@@ -452,13 +452,13 @@ describe("tool conversions", () => {
     });
   });
 
-  it("should handle mcp__acp__read with offset and limit", () => {
+  it("should handle mcp__acp__Read with offset and limit", () => {
     const tool_use = {
       type: "tool_use",
       id: "toolu_01KLM789NOP456",
-      name: "mcp__acp__read",
+      name: "mcp__acp__Read",
       input: {
-        abs_path: "/Users/test/project/large.txt",
+        file_path: "/Users/test/project/large.txt",
         offset: 50,
         limit: 100,
       },
@@ -472,13 +472,13 @@ describe("tool conversions", () => {
     });
   });
 
-  it("should handle mcp__acp__read with only offset", () => {
+  it("should handle mcp__acp__Read with only offset", () => {
     const tool_use = {
       type: "tool_use",
       id: "toolu_01QRS123TUV789",
-      name: "mcp__acp__read",
+      name: "mcp__acp__Read",
       input: {
-        abs_path: "/Users/test/project/large.txt",
+        file_path: "/Users/test/project/large.txt",
         offset: 200,
       },
     };
@@ -539,7 +539,7 @@ describe("tool conversions", () => {
     const tool_use = {
       type: "tool_use",
       id: "toolu_01PhLms5fuvmdjy2bb6dfUKT",
-      name: "KillBash",
+      name: "KillShell",
       input: {
         shell_id: "bash_1",
       },
@@ -701,78 +701,13 @@ describe("tool conversions", () => {
     ]);
   });
 
-  it("should show full diff for multi edit tool", () => {
-    const toolUse = {
-      type: "tool_use",
-      id: "toolu_01DEF456",
-      name: "mcp__acp__multi-edit",
-      input: {
-        file_path: "/Users/test/project/config.json",
-        edits: [
-          {
-            old_string: 'version": 1',
-            new_string: 'version": 2',
-            replace_all: false,
-          },
-          {
-            old_string: 'enabled": false',
-            new_string: 'enabled": true',
-            replace_all: true,
-          },
-        ],
-      },
-    };
-    const fileCache: { [key: string]: string } = {
-      "/Users/test/project/config.json": JSON.stringify(
-        {
-          version: 1,
-          filler: "filler",
-          enabled: false,
-        },
-        null,
-        4,
-      ),
-    };
-
-    expect(toolInfoFromToolUse(toolUse, fileCache)).toEqual({
-      content: [
-        {
-          newText: `{
-    "version": 2,
-    "filler": "filler",
-    "enabled": true
-}`,
-          oldText: `{
-    "version": 1,
-    "filler": "filler",
-    "enabled": false
-}`,
-          path: "/Users/test/project/config.json",
-          type: "diff",
-        },
-      ],
-      kind: "edit",
-      locations: [
-        {
-          path: "/Users/test/project/config.json",
-          line: 1,
-        },
-        {
-          path: "/Users/test/project/config.json",
-          line: 3,
-        },
-      ],
-      title: "Edit /Users/test/project/config.json",
-    });
-  });
-
   it("should return empty update for successful edit result", () => {
     const toolUse = {
       type: "tool_use",
       id: "toolu_01MNO345",
-      name: "mcp__acp__edit",
+      name: "mcp__acp__Edit",
       input: {
-        abs_path: "/Users/test/project/test.txt",
+        file_path: "/Users/test/project/test.txt",
         old_string: "old",
         new_string: "new",
       },
@@ -800,9 +735,9 @@ describe("tool conversions", () => {
     const toolUse = {
       type: "tool_use",
       id: "toolu_01MNO345",
-      name: "mcp__acp__edit",
+      name: "mcp__acp__Edit",
       input: {
-        abs_path: "/Users/test/project/test.txt",
+        file_path: "/Users/test/project/test.txt",
         old_string: "old",
         new_string: "new",
       },
@@ -845,3 +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";
 
@@ -91,8 +86,8 @@ export function toolInfoFromToolUse(
         content: [],
       };
 
-    case "KillBash":
-    case toolNames.killBash:
+    case "KillShell":
+    case toolNames.killShell:
       return {
         title: "Kill Process",
         kind: "execute",
@@ -108,11 +103,11 @@ export function toolInfoFromToolUse(
         limit = " (from line " + (input.offset + 1) + ")";
       }
       return {
-        title: "Read " + (input.abs_path ?? "File") + limit,
+        title: "Read " + (input.file_path ?? "File") + limit,
         kind: "read",
         locations: [
           {
-            path: input.abs_path,
+            path: input.file_path,
             line: input.offset ?? 0,
           },
         ],
@@ -138,7 +133,7 @@ export function toolInfoFromToolUse(
 
     case toolNames.edit:
     case "Edit": {
-      const path = input?.abs_path ?? input?.file_path;
+      const path = input?.file_path ?? input?.file_path;
       let oldText = input.old_string ?? null;
       let newText = input.new_string ?? "";
       let affectedLines: number[] = [];
@@ -182,66 +177,13 @@ export function toolInfoFromToolUse(
       };
     }
 
-    case toolNames.multiEdit:
-    case "MultiEdit": {
-      const multiInput = input as {
-        file_path: string;
-        edits: {
-          old_string: string;
-          new_string: string;
-          replace_all?: boolean;
-        }[];
-      };
-      let oldTextMulti = multiInput.edits.map((edit: any) => edit.old_string).join("\n");
-      let newTextMulti = multiInput.edits.map((edit: any) => edit.new_string).join("\n");
-      let affectedLines: number[] = [];
-      try {
-        if (multiInput.edits && multiInput.file_path) {
-          const oldContent =
-            cachedFileContent[multiInput.file_path] ||
-            multiInput.edits.map((edit: any) => edit.oldText).join("\n");
-          const newContent = replaceAndCalculateLocation(
-            oldContent,
-            multiInput.edits.map((edit) => ({
-              oldText: edit.old_string,
-              newText: edit.new_string,
-              replaceAll: edit.replace_all,
-            })),
-          );
-          oldTextMulti = oldContent;
-          newTextMulti = newContent.newContent;
-          affectedLines = newContent.lineNumbers;
-        }
-      } catch (e) {
-        console.error(e);
-      }
-      // Display it as a normal edit, because end users don't care about
-      // the distinction between edits and multi-edits.
-      return {
-        title: input?.file_path ? `Edit ${input.file_path}` : "Edit",
-        kind: "edit",
-        content: [
-          {
-            type: "diff" as const,
-            path: input.file_path,
-            oldText: oldTextMulti,
-            newText: newTextMulti,
-          },
-        ],
-        locations: input?.file_path
-          ? affectedLines.length > 0
-            ? affectedLines.map((line) => ({ line, path: input.file_path }))
-            : [{ path: input.file_path }]
-          : [],
-      };
-    }
     case toolNames.write: {
       let content: ToolCallContent[] = [];
-      if (input && input.abs_path) {
+      if (input && input.file_path) {
         content = [
           {
             type: "diff",
-            path: input.abs_path,
+            path: input.file_path,
             oldText: null,
             newText: input.content,
           },
@@ -255,10 +197,10 @@ export function toolInfoFromToolUse(
         ];
       }
       return {
-        title: input?.abs_path ? `Write ${input.abs_path}` : "Write",
+        title: input?.file_path ? `Write ${input.file_path}` : "Write",
         kind: "edit",
         content,
-        locations: input?.abs_path ? [{ path: input.abs_path }] : [],
+        locations: input?.file_path ? [{ path: input.file_path }] : [],
       };
     }
 
@@ -481,9 +423,6 @@ export function toolUpdateFromToolResult(
     case "edit":
     case "Edit":
     case toolNames.edit:
-    case toolNames.multiEdit:
-    case "multi-edit":
-    case "MultiEdit":
     case toolNames.write:
     case "Write": {
       if (toolResult.is_error && toolResult.content && toolResult.content.length > 0) {