[Bug] Anthropic API Error: chatParticipant must be declared in package.json

Bug Description
I can't get claude code to run in the sidebar mode, forced to run in terminal mode. Developer tools show ERR chatParticipant must be declared in package.json: claude-code
error @ log.ts:460

Environment Info

• Platform: darwin
• Terminal: vscode
• Version: 2.0.21
• Feedback ID: c8649433-55b5-4b3e-bfb1-b926f8e38193

Errors

[{"error":"SyntaxError: Unexpected token '`', \"```json\n{\n\"... is not valid JSON\n    at JSON.parse (<anonymous>)\n    at file:///opt/homebrew/lib/node_modules/@anthropic-ai/claude-code/cli.js:62:719\n    at Q (file:///opt/homebrew/lib/node_modules/@anthropic-ai/claude-code/cli.js:8:15093)\n    at Zn2 (file:///opt/homebrew/lib/node_modules/@anthropic-ai/claude-code/cli.js:1056:20444)\n    at process.processTicksAndRejections (node:internal/process/task_queues:105:5)","timestamp":"2025-10-17T08:33:10.184Z"},{"error":"SyntaxError: Unexpected token '`', \"```json\n{\n\"... is not valid JSON\n    at JSON.parse (<anonymous>)\n    at file:///opt/homebrew/lib/node_modules/@anthropic-ai/claude-code/cli.js:62:719\n    at Q (file:///opt/homebrew/lib/node_modules/@anthropic-ai/claude-code/cli.js:8:15093)\n    at Zn2 (file:///opt/homebrew/lib/node_modules/@anthropic-ai/claude-code/cli.js:1056:20444)\n    at process.processTicksAndRejections (node:internal/process/task_queues:105:5)","timestamp":"2025-10-17T08:34:04.684Z"},{"error":"Error: Language not supported while highlighting code, falling back to markdown: \n    at mD (file:///opt/homebrew/lib/node_modules/@anthropic-ai/claude-code/cli.js:1140:4413)\n    at file:///opt/homebrew/lib/node_modules/@anthropic-ai/claude-code/cli.js:1140:4141\n    at Array.map (<anonymous>)\n    at WV (file:///opt/homebrew/lib/node_modules/@anthropic-ai/claude-code/cli.js:1140:4132)\n    at o5Q (file:///opt/homebrew/lib/node_modules/@anthropic-ai/claude-code/cli.js:2202:17128)\n    at m$ (file:///opt/homebrew/lib/node_modules/@anthropic-ai/claude-code/cli.js:73:19414)\n    at ps (file:///opt/homebrew/lib/node_modules/@anthropic-ai/claude-code/cli.js:75:42814)\n    at y9 (file:///opt/homebrew/lib/node_modules/@anthropic-ai/claude-code/cli.js:75:38355)\n    at Dd (file:///opt/homebrew/lib/node_modules/@anthropic-ai/claude-code/cli.js:75:38283)\n    at t$ (file:///opt/homebrew/lib/node_modules/@anthropic-ai/claude-code/cli.js:75:38137)","timestamp":"2025-10-17T08:35:14.978Z"}]