fix(core): harden env loading, OpenAI compatibility, and runtime recovery

src/backends/native/agent.ts

@@ -260,6 +260,13 @@ export class NativeAgent {
             }
           }
         }
+        if (toolCalls.length === 0) {
+          const recovered = this.extractMalformedShellToolCall(response.content);
+          if (recovered && toolRegistry.getByApiName(recovered.toolCall.name)) {
+            toolCalls = [recovered.toolCall];
+            assistantTextContent = recovered.remainingText;
+          }
+        }
 
         const wantsToolUse = toolCalls.length > 0;
         if (!wantsToolUse) {
@@ -705,6 +712,94 @@ export class NativeAgent {
     };
   }
 
+  private extractMalformedShellToolCall(content: string): { toolCall: ModelToolCall; remainingText: string } | null {
+    if (!content || !/"type"\s*:\s*"tool_use"/.test(content)) {
+      return null;
+    }
+
+    const nameMatch = content.match(/"name"\s*:\s*"([^"]+)"/);
+    if (!nameMatch?.[1]) {
+      return null;
+    }
+    const name = nameMatch[1];
+    const normalized = name.replace(/_/g, '.').toLowerCase();
+    if (normalized !== 'shell.exec') {
+      return null;
+    }
+
+    // Recover malformed shell command payloads where inner quotes are not escaped.
+    const commandMatch = content.match(/"command"\s*:\s*"([\s\S]*)"\s*}\s*}/);
+    if (!commandMatch?.[1]) {
+      return null;
+    }
+
+    const command = this.sanitizeRecoveredShellCommand(commandMatch[1]);
+    if (!command) {
+      return null;
+    }
+
+    const idMatch = content.match(/"id"\s*:\s*"([^"]+)"/);
+    const id = idMatch?.[1]?.trim().length ? idMatch[1] : 'text_tool_call_recovered_shell';
+
+    return {
+      toolCall: {
+        id,
+        name,
+        args: { command },
+      },
+      remainingText: this.stripFirstToolUseObject(content),
+    };
+  }
+
+  private sanitizeRecoveredShellCommand(raw: string): string {
+    let command = raw.trim();
+    if (command.length === 0) {
+      return '';
+    }
+
+    // Common malformed pattern: opening quote duplicated into value.
+    if ((command.startsWith('"') && !command.endsWith('"')) || (command.startsWith('\'') && !command.endsWith('\''))) {
+      command = command.slice(1).trimStart();
+    }
+
+    return command;
+  }
+
+  private stripFirstToolUseObject(content: string): string {
+    const typeMatch = /"type"\s*:\s*"tool_use"/.exec(content);
+    if (!typeMatch || typeMatch.index < 0) {
+      return content.trim();
+    }
+
+    const objectStart = content.lastIndexOf('{', typeMatch.index);
+    if (objectStart < 0) {
+      return content.trim();
+    }
+
+    const objectEnd = this.findObjectEndByBraceDepth(content, objectStart);
+    if (objectEnd < 0) {
+      return content.trim();
+    }
+
+    return `${content.slice(0, objectStart)}${content.slice(objectEnd + 1)}`.trim();
+  }
+
+  private findObjectEndByBraceDepth(content: string, start: number): number {
+    let depth = 0;
+    for (let i = start; i < content.length; i++) {
+      const ch = content[i];
+      if (ch === '{') {
+        depth++;
+      } else if (ch === '}') {
+        depth--;
+        if (depth === 0) {
+          return i;
+        }
+      }
+    }
+    return -1;
+  }
+
   private findJsonObjectEnd(content: string, start: number): number {
     let depth = 0;
     let inString = false;