Claude Code Prompt Improver v0.5.3: Plan Mode Refactor and Subagent-First Research

v0.5.3 of the Claude Code Prompt Improver is out, past 1.4K stars on GitHub. The plugin hooks into UserPromptSubmit to check if a prompt is vague before Claude Code runs it — clear prompts pass through, vague ones trigger a prompt-improver skill that researches the codebase and asks 1–6 questions via AskUserQuestion. The hook adds ~189 tokens per prompt.

Plan Mode Readability (v0.5.3)

A new PreToolUse hook runs on EnterPlanMode. Plans were accumulating revision history — lines like "previously I considered X but rejected it because Y". The hook tells the model to:

• Keep only the problem statement, remove decision history
• On revisions, rewrite the full plan cleanly — do not append or annotate
• One action per step, using file paths as anchors (e.g., src/auth.ts:42)
• Use short action steps, not long explanations

Subagent-First Research (v0.5.2)

Previously, vague prompts triggered Glob, Grep, WebSearch, and other search tools directly in the main context, burning main-model tokens. Now those tools run through Task/Explore subagents on Haiku, using a separate context window. The main context only handles git commands, single-file reads of user-named files, synthesis, and the final question to the user.

Maintenance (v0.5.0 & v0.5.1)

• Marketplace renamed from claude-code-marketplace to severity1-marketplace
• Hook command uses python3 || python for Windows compatibility
• CLAUDE.md uses auto-memory format

Install

claude plugin marketplace add severity1/severity1-marketplace
claude plugin install prompt-improver@severity1-marketplace

Repository

github.com/severity1/claude-code-prompt-improver