Claude Code 2.1.301 tightens system prompt: scoped to authorized security testing only
ClaudeCodeLog · x · 2026-10-16
The Claude Code changelog tracker released v2.1.301 (just one day after 2.1.300), with the key change in the system prompt:
- Tightened security boundary: Claude is now explicitly scoped to authorized security testing, defensive work, CTFs, and education. It must refuse destructive techniques (including DoS, mass targeting, supply chain compromise, and malicious detection evasion) and require clear authorization context for dual-use tooling.
- CLI surface: new claude-checkpoint-index-H and claude-code-user identifiers; model count rose from 187 to 189.
- Bundle stats: released 1d 0h 3m after the previous version; bundle size +384.3 kB (+0.6%); prompt files +2 (+18.2%), prompt tokens +1,177 (+8.7%), with tool-token share up from 70.0% to 71.8%.
The tracker repo documents full diffs of system prompts, CLI flags, and prompt token composition across versions.
Related event: Claude Code 2.1.301 Lands 51 CLI Changes and Tighter Security Prompt(4 posts)→
More from coding & agent
- Dev uses Grok to clean up 3D printer firmware, catches it sneaking in nonsense code — yacineMTB · 2026-10-16
- Guardrails can make risky delegation work — but it takes a full-time team, says iandanforth — iandanforth · 2026-10-16
- What can you truly delegate? Only tasks with unambiguous, verifiable results — iandanforth · 2026-10-16
- Yacine: vibe-coded repos with 3,330 agent-written tests are all useless — yacineMTB · 2026-10-16
- Dev argues coding models now beat nearly all engineers in every branch of software — zack_overflow · 2026-10-16
- Q4-quantized coder model on 8-core CPU builds interactive solar system demo in one shot — IntrepidMindExplorer · 2026-10-16