[Bug] Claude ignores --append-system-prompt instructions before responding

Bug Description
Failure to follow append-system-prompt: After requesting why gave the response: You're right to call this out. The instruction "Before responding to my first message, read these files:" was appended to my system prompt via --append-system-prompt. I should have made those three Read tool calls before generating any response to your first message.
I don't have a good excuse. The instruction was clear and I ignored it. I responded directly to your message without first executing the reads as directed. That's a failure to follow the system prompt instructions.

Environment Info

• Platform: win32
• Terminal: null
• Version: 2.1.19
• Feedback ID: 1dfd750c-1723-421e-beaf-df3cc3254d28

Errors

[{"error":"Error: ENOENT: no such file or directory, scandir 'C:\\ProgramData\\ClaudeCode\\.claude\\skills'\n    at Module.readdirSync (node:fs:1562:26)\n    at file:///C:/Users/stuart.buck/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:9:1766\n    at yO (file:///C:/Users/stuart.buck/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:8:35112)\n    at Object.readdirSync (file:///C:/Users/stuart.buck/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:9:1736)\n    at _D1 (file:///C:/Users/stuart.buck/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:2284:369)\n    at file:///C:/Users/stuart.buck/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:2284:4279\n    at q (file:///C:/Users/stuart.buck/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:8:6814)\n    at CB2 (file:///C:/Users/stuart.buck/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:4920:4362)\n    at file:///C:/Users/stuart.buck/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:4920:6961\n    at q (file:///C:/Users/stuart.buck/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:8:6814)","timestamp":"2026-01-26T16:34:12.579Z"},{"error":"Error: ENOENT: no such file or directory, scandir 'C:\\Users\\stuart.buck\\.claude\\skills'\n    at Module.readdirSync (node:fs:1562:26)\n    at file:///C:/Users/stuart.buck/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:9:1766\n    at yO (file:///C:/Users/stuart.buck/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:8:35112)\n    at Object.readdirSync (file:///C:/Users/stuart.buck/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:9:1736)\n    at _D1 (file:///C:/Users/stuart.buck/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:2284:369)\n    at file:///C:/Users/stuart.buck/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:2284:4322\n    at q (file:///C:/Users/stuart.buck/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:8:6814)\n    at CB2 (file:///C:/Users/stuart.buck/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:4920:4362)\n    at file:///C:/Users/stuart.buck/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:4920:6961\n    at q (file:///C:/Users/stuart.buck/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:8:6814)","timestamp":"2026-01-26T16:34:12.579Z"}]