Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx agentmods add commands/sergei-aronsen/claude-code-toolkit/prompt-engineergit clone --depth 1 https://github.com/sergei-aronsen/claude-code-toolkitWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/commands/sergei-aronsen/claude-code-toolkit/prompt-engineer)<a href="https://agentmods.dev/commands/sergei-aronsen/claude-code-toolkit/prompt-engineer"><img src="https://agentmods.dev/badge/commands/sergei-aronsen/claude-code-toolkit/prompt-engineer.svg" alt="Measured on agentmods" height="20"></a>What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5 | $0.00000 | $0.02396 |
| Opus 5 | $0.00000 | $0.01198 |
| Sonnet 5 | $0.00000 | $0.00479 |
| Haiku 4.5 | $0.00000 | $0.00240 |
Grade A, and why
prompt-engineer scanned grade A with 1 finding against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 4d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Makes network callslowCapability
Not a fault in itself. Listed so you know the mod talks to something, and to what.
bash <(curl -sSL https://raw.githubusercontent.com/sergei-aronsen/claude-code-toolkit/main/scripts/setup-prompt-engineer.sh) How it starts
The opening of the file, as written. The whole thing — 271 lines — stays where its author put it; the contents beside it link to each section on GitHub.
/prompt-engineer — Single-Prompt Optimizer (multi-provider)
Purpose
Rewrite a single prompt file into a deployment-ready version. Companion
to /council — where the Council validates a plan with Skeptic +
Pragmatist review, the Prompt Engineer rewrites one prompt for clarity,
controllability, reliability, and reusability. Drives one of three
provider CLIs: Claude Code (claude -p), Codex (codex exec),
or Gemini (gemini -p). --provider all runs all three in
parallel and synthesizes a best-of final.
Usage
/prompt-engineer <path-to-prompt-file>
/prompt-engineer <path-to-prompt-file> --provider claude
/prompt-engineer <path-to-prompt-file> --provider all
/prompt-engineer <path-to-prompt-file> --context <context-file>
/prompt-engineer <path-to-prompt-file> --multi-pass
/prompt-engineer <path-to-prompt-file> --log
Examples:
/prompt-engineer prompts/code-review.md --provider claude/prompt-engineer agents/security-auditor.md --context project-context.md --provider all/prompt-engineer my-prompt.md --multi-pass --provider codex
Or use the installed shell alias directly:
pe path/to/prompt.md # interactive menu
pe path/to/prompt.md --provider claude
pe path/to/prompt.md --provider all --log
pe path/to/prompt.md --context path/to/context.md
echo "Write me a tone-control prompt" | pe - --provider claude
Provider (--provider)
| Value | CLI invoked | Notes |
|---|---|---|
claude |
claude -p (stdin) |
Best instruction-following on long system prompts. |
codex |
codex exec --skip-git-repo-check -o tmp - |
Tight, terse rewrites. |
gemini |
gemini -p "" (stdin) |
Fast. Output sometimes lacks fenced block. |
all |
claude + codex + gemini in parallel, then 1 synthesis call | 4 calls total. Synthesizer preference: claude > codex > gemini. |
ask |
Interactive menu on TTY; falls back to claude when stdin is not a TTY |
Default. |
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 4d ago First seen · 271 lines · 0 tokens per session scan A da9a9bd29859
prompt-engineer is a command published in the GitHub repository sergei-aronsen/claude-code-toolkit (5 stars, last pushed 18d ago), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 2,396 tokens. A static security scan graded it A with 1 finding (makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.
Other commands, from other repositories
prompt
System instructions for writing effective prompts. Apply when generating commands, skills, agents, or any LLM instructions.
prompt-show
Display full details of a saved prompt by ID.
music-suno-prompt
Grounded Suno prompt synthesis from local knowledge corpus + persona canon + label canon. No vibes-prompting.
prompt-optimize
Present the efficiency-versus-effectiveness frontier as labelled variants and let the user pick. TRIGGER WHEN: the user wants to review or optimize a prompt, system message, or agent instructions for clarity/tokens/reliability.
audit-prompt
Evaluate an existing prompt for clarity, effectiveness, and edge cases.
develop-image-prompt.eval
Generates a detailed image generation prompt from a document or content description. Good output: a prompt that is specific, visual, non-abstract, includes style/composition/lighting guidance, and is calibrated to the specified dimensions and style options.