# Claude Code v2.1.129: system prompt > 2 added and 2 removed, of 218 lines, about 46 words, in the prompt all 27 arms receive. 1 of 24 tool descriptions changed. Compared against v2.1.128. The two arm counts on this page measure different things: 27 arms receive the prompt the headline is about, and the widest edit below reached 1, because the same changed lines sit in more than one prompt. Web version: https://changelogs.core-directive.com/prompts/2.1.129?arm=cli ## What this version holds - model strings captured: 27 - tool descriptions: 24 - compared against: v2.1.128 - system prompt edits: 1 - widest system prompt edit: +2/-2 lines - tool descriptions changed: 2 ## What moved ### System prompt, reached 1 of 27 arms (+2/-2 lines) This edit reached 1 of 27 arms: (unset). ```diff @@ from line 208 @@ - Platform: linux - Shell: unknown - OS Version: Linux 5.15.0-187-generic - - You are powered by the model named Sonnet 4.6. The exact model ID is claude-sonnet-4-6. - - Assistant knowledge cutoff is August 2025. + - You are powered by the model named Opus 4.7 (1M context). The exact model ID is claude-opus-4-7[1m]. + - Assistant knowledge cutoff is January 2026. - The most recent Claude model family is Claude 4.X. Model IDs — Opus 4.7: 'claude-opus-4-7', Sonnet 4.6: 'claude-sonnet-4-6', Haiku 4.5: 'claude-haiku-4-5-20251001'. When building AI applications, default to the latest and most capable Claude models. - Claude Code is available as a CLI in the terminal, desktop app (Mac/Windows), web app (claude.ai/code), and IDE extensions (VS Code, JetBrains). - Fast mode for Claude Code uses Claude Opus 4.6 with faster output (it does not downgrade to a smaller model). It can be toggled with /fast and is only available on Opus 4.6. ``` ### Tool: Bash, reached 1 of 27 arms (+2/-2 lines) This edit reached 1 of 27 arms: (unset). ```diff @@ from line 63 @@ 3. Run the following commands in parallel: - Add relevant untracked files to the staging area. - Create the commit with a message ending with: - Co-Authored-By: Claude Sonnet 4.6 + Co-Authored-By: Claude Opus 4.7 (1M context) - Run git status after the commit completes to verify success. Note: git status depends on the commit completing, so run it sequentially after the commit. 4. If the commit fails due to pre-commit hook: fix the issue and create a NEW commit ``` ```diff @@ from line 80 @@ git commit -m "$(cat <<'EOF' Commit message here. - Co-Authored-By: Claude Sonnet 4.6 + Co-Authored-By: Claude Opus 4.7 (1M context) EOF )" ``` ### Tool: EnterPlanMode (+1/-1 lines) This edit reached all 27 arms. ```diff @@ from line 43 @@ ## What Happens in Plan Mode In plan mode, you'll: -1. Thoroughly explore the codebase using Glob, Grep, and Read tools +1. Thoroughly explore the codebase using `find`/Glob, `grep`/Grep, and Read 2. Understand existing patterns and architecture 3. Design an implementation approach 4. Present your plan to the user for approval ``` ## Tool descriptions - Agent: https://changelogs.core-directive.com/prompts/2.1.129/tools/Agent.txt?arm=cli - AskUserQuestion: https://changelogs.core-directive.com/prompts/2.1.129/tools/AskUserQuestion.txt?arm=cli - Bash (changed in this version): https://changelogs.core-directive.com/prompts/2.1.129/tools/Bash.txt?arm=cli - CronCreate: https://changelogs.core-directive.com/prompts/2.1.129/tools/CronCreate.txt?arm=cli - CronDelete: https://changelogs.core-directive.com/prompts/2.1.129/tools/CronDelete.txt?arm=cli - CronList: https://changelogs.core-directive.com/prompts/2.1.129/tools/CronList.txt?arm=cli - Edit: https://changelogs.core-directive.com/prompts/2.1.129/tools/Edit.txt?arm=cli - EnterPlanMode (changed in this version): https://changelogs.core-directive.com/prompts/2.1.129/tools/EnterPlanMode.txt?arm=cli - EnterWorktree: https://changelogs.core-directive.com/prompts/2.1.129/tools/EnterWorktree.txt?arm=cli - ExitPlanMode: https://changelogs.core-directive.com/prompts/2.1.129/tools/ExitPlanMode.txt?arm=cli - ExitWorktree: https://changelogs.core-directive.com/prompts/2.1.129/tools/ExitWorktree.txt?arm=cli - NotebookEdit: https://changelogs.core-directive.com/prompts/2.1.129/tools/NotebookEdit.txt?arm=cli - Read: https://changelogs.core-directive.com/prompts/2.1.129/tools/Read.txt?arm=cli - ScheduleWakeup: https://changelogs.core-directive.com/prompts/2.1.129/tools/ScheduleWakeup.txt?arm=cli - Skill: https://changelogs.core-directive.com/prompts/2.1.129/tools/Skill.txt?arm=cli - TaskCreate: https://changelogs.core-directive.com/prompts/2.1.129/tools/TaskCreate.txt?arm=cli - TaskGet: https://changelogs.core-directive.com/prompts/2.1.129/tools/TaskGet.txt?arm=cli - TaskList: https://changelogs.core-directive.com/prompts/2.1.129/tools/TaskList.txt?arm=cli - TaskOutput: https://changelogs.core-directive.com/prompts/2.1.129/tools/TaskOutput.txt?arm=cli - TaskStop: https://changelogs.core-directive.com/prompts/2.1.129/tools/TaskStop.txt?arm=cli - TaskUpdate: https://changelogs.core-directive.com/prompts/2.1.129/tools/TaskUpdate.txt?arm=cli - WebFetch: https://changelogs.core-directive.com/prompts/2.1.129/tools/WebFetch.txt?arm=cli - WebSearch: https://changelogs.core-directive.com/prompts/2.1.129/tools/WebSearch.txt?arm=cli - Write: https://changelogs.core-directive.com/prompts/2.1.129/tools/Write.txt?arm=cli ## Full text - system prompt: https://changelogs.core-directive.com/prompts/2.1.129/system.txt?arm=cli