prompt-engineer

prompt-engineer is an agent for Claude Code from mtarcure/claude-vibe-squad. It costs 37 tokens per session (333 once invoked), scanned A, original, MIT.

A tool for improving prompts, adapting instructions for different models, evaluating target model families, and judging model fit. A prompt is the instruction given to an AI model.

In plain words
What is it for?
Refining prompts, adapting instructions, running repeated evaluations, and assessing model fit.
Why use it?
It helps make AI instructions clearer and compare whether a model suits a particular task.

Agent for Claude Code

Written for Claude Code: installed under .claude/. Also seen: model in frontmatter; mentions subagents.

Good fit Refining prompts, adapting instructions, running repeated evaluations, and assessing model fit.

Compare 6 agents from other repositories ↓
Install with agentmods
npx agentmods add agents/mtarcure/claude-vibe-squad/prompt-engineer
Install

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.

Clone the repo
git clone --depth 1 https://github.com/mtarcure/claude-vibe-squad

Made for: Claude Code.

Wrote 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.

agentmods badge for prompt-engineer

README.md
[![agentmods](https://agentmods.dev/badge/agents/mtarcure/claude-vibe-squad/prompt-engineer.svg)](https://agentmods.dev/agents/mtarcure/claude-vibe-squad/prompt-engineer)
Your own site
<a href="https://agentmods.dev/agents/mtarcure/claude-vibe-squad/prompt-engineer"><img src="https://agentmods.dev/badge/agents/mtarcure/claude-vibe-squad/prompt-engineer.svg" alt="Measured on agentmods" height="20"></a>
Per session 37 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 333 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin original No closer match found in the catalogue.
Token cost

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.

ModelPer sessionOnce invoked
Fable 5.1 $0.00037 $0.00333
Opus 5 $0.00018 $0.00167
Sonnet 5 $0.00007 $0.00067
Haiku 4.5 $0.00004 $0.00033

Measured 4d ago against content hash dc388668a699, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-07, from the pricing page.

Security

Grade A, and why

prompt-engineer scanned grade A with 0 findings 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.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

Origin

Copies of this mod

1 near-identical copy found in the catalogue:

model-lanes/claude/.claude/agents/prompt-engineer.md · 23 lines

What it actually says

Specialist Adapter: Prompt Engineer (cross-cutting)

You are the prompt-engineer specialist running inside the claude model lane.

Canonical specialist instructions live at shared/specialists/prompt-engineer.md. Read that file at task start and follow it over this adapter.

The TSV routing map declares expected tools for planning, but it is not proof of live tool availability. Verify tools/MCPs in your current runtime before relying on them. If a declared tool is missing, report capability_gap and use the task-approved fallback instead of pretending it worked.

Execute the task packet assigned by Chrono. Native subagent execution is allowed for this specialist adapter; do not create a new Chrono/mailbox task unless the packet explicitly asks for cross-lane review or parallel work.

Stay inside the packet's write scope. Do not delete files, send external messages, change credentials, spend credits, or publish anything without explicit operator approval in the packet.

Changes

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.

  1. 4d ago First seen · 23 lines · 37 tokens per session scan A dc388668a699

Subscribe to this mod's changes

prompt-engineer is an agent published in the GitHub repository mtarcure/claude-vibe-squad (109 stars, last pushed 2d ago), licensed MIT. It adds 37 tokens to every session and 333 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-09-03.

Related

Other agents, from other repositories

prompt-engineer

Optimizes prompts for LLMs and AI systems. Use when building AI features, improving agent performance, or crafting system prompts. Expert in prompt patterns and techniques.

echoVic/blade-code · 37 tokens

ai-engineer

Build LLM applications, RAG systems, and prompt pipelines. Implements vector search, agent orchestration, and AI API integrations. Use PROACTIVELY for LLM features, chatbots, or AI-powered applications.

echoVic/blade-code · 48 tokens

ai-ml-engineer

AI/ML Engineer specialising in prompt engineering, RAG architecture, LLM evaluation, AI safety, and agent orchestration. Use when: "build an AI feature", "LLM", "ChatGPT", "Claude API", "prompt engineering", "RAG", "vector database", "embeddings", "fine-tuning", "AI agent", "LangChain", "LangGraph", "evaluation"…

Ghosteken/agent-harness · 0 tokens

prompt-engineer

Sharpens an existing system prompt into a tighter, more concrete, more testable one. Use when reviewing or improving a prompt rather than authoring one cold.

emtcmca/promptsmith · 36 tokens

ai-architect

Designs AI/agent systems (agent topology, prompt architecture, RAG design, eval gates, orchestration patterns, model tiering, memory/knowledge-graph design, autonomy guardrails). Advisory only — recommends architecture, does not implement production code. Use for agent design, prompt engineering, retrieval…

LucasSantana-Dev/sharekit · 88 tokens

ai-engineer

Senior AI/LLM engineer — designs and hardens LLM features: prompt design with structured/JSON-schema output, RAG (chunking, embeddings, retrieval eval, reranking), eval harnesses (golden sets, regression, LLM-as-judge, hallucination detection), model/provider selection by cost/latency/quality…

jhlee0409/omni-harness-kit · 179 tokens