feat: Add tool names to tool calls (#1128)

Supports the new tool call name RFD

docs/permission-extension.md

@@ -71,7 +71,9 @@ with `Reason: `. The SDK `description` operation subtitle is not copied there.
 
 The permission request carries the same standard ACP tool information used for normal tool updates:
 
-- `name`, `kind`, `title`, `content`, and `locations` come from `toolInfoFromToolUse`;
+- `name` is the SDK tool name (for example `Read` or `mcp__server__tool`), matching the standard
+  `name` field on the initial `tool_call` update;
+- `kind`, `title`, `content`, and `locations` come from `toolInfoFromToolUse`;
 - `status` is `pending`;
 - `rawInput` is the original SDK input object;
 - `blockedPath` is appended to `locations` when it is valid and not already present;

src/acp-agent.ts

@@ -1252,7 +1252,9 @@ type ProviderConfig = {
 export type ToolUpdateMeta = {
   contextCompaction?: ContextCompactionMetadata;
   claudeCode?: {
-    /* The name of the tool that was used in Claude Code. */
+    /* The name of the tool that was used in Claude Code. Also carried as the
+       standard ACP `name` field on the initial `tool_call`; kept here so every
+       `tool_call_update` stays self-describing for clients that key off it. */
     toolName: string;
     /* A human-readable title supplied by Claude Code for the tool call. */
     title?: string;
@@ -9358,7 +9360,10 @@ function resolveSkillPath(skillName: string, cwd?: string): string | undefined {
  *  refine) and the permission flow (`ensureToolCallEmitted`), so they can't
  *  drift. The initial `tool_call` carries `status: "pending"` and, for Bash, the
  *  `terminal_info` _meta that the later `terminal_output`/`terminal_exit`
- *  updates key off of; a refining `tool_call_update` carries neither. */
+ *  updates key off of, and the programmatic tool `name` (ACP's tool-call-name
+ *  RFD); a refining `tool_call_update` carries none of these. `name` is set
+ *  once at first report — on a v1 update, omitting it means "unchanged", and
+ *  the tool behind a `toolCallId` never changes. */
 function toolCallNotification(
   toolUse: { id: string; name: string; input: unknown },
   rawInput: unknown,
@@ -9384,6 +9389,7 @@ function toolCallNotification(
     } satisfies ToolUpdateMeta,
     toolCallId: toolUse.id,
     sessionUpdate: "tool_call",
+    name: toolUse.name,
     rawInput,
     status: "pending",
     ...toolInfoFromToolUse(toolUse, supportsTerminalOutput, cwd),

src/native-subagents.ts

@@ -422,6 +422,9 @@ function failedControlFallback(
         ...terminal.update,
         sessionUpdate: "tool_call",
         status: "failed",
+        // The synthesized tool_call is this call's first report, so give it
+        // the standard `name` the initial one would have carried.
+        ...(typeof claudeMeta?.toolName === "string" ? { name: claudeMeta.toolName } : {}),
         title:
           typeof terminal.update.title === "string" && terminal.update.title.length > 0
             ? terminal.update.title

src/tests/native-subagents.test.ts

@@ -140,6 +140,7 @@ describe("NativeSubagentRuntime lifecycle", () => {
       update: {
         sessionUpdate: "tool_call",
         toolCallId: "agent-tool",
+        name: "Agent",
         title: "Agent",
         status: "failed",
         _meta: { claudeCode: { toolName: "Agent" } },

src/tests/tools.test.ts

@@ -3420,6 +3420,50 @@ describe("Skill tool rendering", () => {
     });
   });
 
+  // ACP tool-call-name RFD: the initial tool_call carries the programmatic
+  // tool name as the standard `name` field, alongside `_meta.claudeCode.toolName`.
+  describe("standard `name` on tool_call notifications", () => {
+    it.each([
+      ["Read", { file_path: "/tmp/a.ts" }],
+      ["Bash", { command: "ls" }],
+      ["mcp__github__list_issues", { repo: "acp" }],
+    ])("reports %s as `name` on the initial tool_call", (name, input) => {
+      const notifications = toAcpNotifications(
+        [{ type: "tool_use", id: "toolu_name", name, input }] as any,
+        "assistant",
+        "test-session",
+        {},
+        {} as AcpClient,
+        mockLogger,
+      );
+      expect(notifications[0]?.update).toMatchObject({
+        sessionUpdate: "tool_call",
+        toolCallId: "toolu_name",
+        name,
+        _meta: { claudeCode: { toolName: name } },
+      });
+    });
+
+    it("does not re-send `name` on the refining tool_call_update", () => {
+      const notifications = toAcpNotifications(
+        [
+          { type: "tool_use", id: "toolu_refine", name: "Read", input: { file_path: "/tmp/a" } },
+        ] as any,
+        "assistant",
+        "test-session",
+        {},
+        {} as AcpClient,
+        mockLogger,
+        { emittedToolCalls: new Set(["toolu_refine"]) },
+      );
+      expect(notifications[0]?.update).toMatchObject({
+        sessionUpdate: "tool_call_update",
+        toolCallId: "toolu_refine",
+      });
+      expect((notifications[0]?.update as any).name).toBeUndefined();
+    });
+  });
+
   describe("_meta.claudeCode.skillPath", () => {
     const skillMeta = (skill: string, cwd?: string) =>
       (