chore(main): release 0.31.1 (#600)

🤖 I have created a release *beep* *boop*
---


##
[0.31.1](https://github.com/agentclientprotocol/claude-agent-acp/compare/v0.31.0...v0.31.1)
(2026-04-27)


### Bug Fixes

* detect glibc and use correct binary
([#599](https://github.com/agentclientprotocol/claude-agent-acp/issues/599))
([f0801d5](f0801d50b2))

---
This PR was generated with [Release
Please](https://github.com/googleapis/release-please). See
[documentation](https://github.com/googleapis/release-please#release-please).

Co-authored-by: acp-release-bot[bot] <246668977+acp-release-bot[bot]@users.noreply.github.com>

.release-please-manifest.json

@@ -1,3 +1,3 @@
 {
-  ".": "0.31.0"
+  ".": "0.31.1"
 }

CHANGELOG.md

@@ -1,5 +1,12 @@
 # Changelog
 
+## [0.31.1](https://github.com/agentclientprotocol/claude-agent-acp/compare/v0.31.0...v0.31.1) (2026-04-27)
+
+
+### Bug Fixes
+
+* detect glibc and use correct binary ([#599](https://github.com/agentclientprotocol/claude-agent-acp/issues/599)) ([f0801d5](https://github.com/agentclientprotocol/claude-agent-acp/commit/f0801d50b2390a3c48150b9b8507d30a70c18b84))
+
 ## [0.31.0](https://github.com/agentclientprotocol/claude-agent-acp/compare/v0.30.0...v0.31.0) (2026-04-24)
 
 

package-lock.json

@@ -1,12 +1,12 @@
 {
   "name": "@agentclientprotocol/claude-agent-acp",
-  "version": "0.31.0",
+  "version": "0.31.1",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "@agentclientprotocol/claude-agent-acp",
-      "version": "0.31.0",
+      "version": "0.31.1",
       "license": "Apache-2.0",
       "dependencies": {
         "@agentclientprotocol/sdk": "0.20.0",

package.json

@@ -3,7 +3,7 @@
   "publishConfig": {
     "access": "public"
   },
-  "version": "0.31.0",
+  "version": "0.31.1",
   "description": "An ACP-compatible coding agent powered by the Claude Agent SDK (TypeScript)",
   "main": "dist/lib.js",
   "types": "dist/lib.d.ts",

src/acp-agent.ts

@@ -274,12 +274,22 @@ export async function claudeCliPath(): Promise<string> {
   const { createRequire } = await import("node:module");
   const req = createRequire(import.meta.resolve("@anthropic-ai/claude-agent-sdk"));
   const ext = process.platform === "win32" ? ".exe" : "";
+  // On linux, both glibc and musl variants may be installed side-by-side
+  // (e.g. bunx hydrates every optional dep), so picking one by trial is
+  // unreliable: the wrong binary segfaults at runtime instead of failing to
+  // spawn. Detect the runtime libc and prefer the matching variant, falling
+  // back to the other only if the preferred one isn't installed.
   const candidates =
     process.platform === "linux"
-      ? [
-          `@anthropic-ai/claude-agent-sdk-linux-${process.arch}-musl/claude${ext}`,
-          `@anthropic-ai/claude-agent-sdk-linux-${process.arch}/claude${ext}`,
-        ]
+      ? isMuslLibc()
+        ? [
+            `@anthropic-ai/claude-agent-sdk-linux-${process.arch}-musl/claude${ext}`,
+            `@anthropic-ai/claude-agent-sdk-linux-${process.arch}/claude${ext}`,
+          ]
+        : [
+            `@anthropic-ai/claude-agent-sdk-linux-${process.arch}/claude${ext}`,
+            `@anthropic-ai/claude-agent-sdk-linux-${process.arch}-musl/claude${ext}`,
+          ]
       : [`@anthropic-ai/claude-agent-sdk-${process.platform}-${process.arch}/claude${ext}`];
   for (const candidate of candidates) {
     try {
@@ -294,6 +304,15 @@ export async function claudeCliPath(): Promise<string> {
   );
 }
 
+function isMuslLibc(): boolean {
+  // process.report.getReport().header.glibcVersionRuntime is populated when
+  // Node is dynamically linked against glibc, and absent on musl.
+  const report = process.report?.getReport() as
+    | { header?: { glibcVersionRuntime?: string } }
+    | undefined;
+  return !report?.header?.glibcVersionRuntime;
+}
+
 function shouldHideClaudeAuth(): boolean {
   return process.argv.includes("--hide-claude-auth");
 }
@@ -1760,7 +1779,7 @@ export class ClaudeAcpAgent implements Agent {
       allowDangerouslySkipPermissions: ALLOW_BYPASS,
       permissionMode,
       canUseTool: this.canUseTool(sessionId),
-      pathToClaudeCodeExecutable: process.env.CLAUDE_CODE_EXECUTABLE,
+      pathToClaudeCodeExecutable: process.env.CLAUDE_CODE_EXECUTABLE ?? (await claudeCliPath()),
       extraArgs: {
         ...userProvidedOptions?.extraArgs,
         "replay-user-messages": "",