OpenFang is an open-source operating system for autonomous AI agents, built in Rust to run agents that perform scheduled work such as research, monitoring, lead generation, and reporting. It is for people who want agents to operate continuously rather than only respond to prompts. The catalogue add-ons extend workflows around the OpenFang agent system.
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 skills add RightNow-AI/openfang --skill prompt-engineergit clone --depth 1 https://github.com/RightNow-AI/openfangWrote 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/skills/rightnow-ai/openfang/prompt-engineer)<a href="https://agentmods.dev/skills/rightnow-ai/openfang/prompt-engineer"><img src="https://agentmods.dev/badge/skills/rightnow-ai/openfang/prompt-engineer/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/rightnow-ai/openfang/prompt-engineer"><img src="https://agentmods.dev/badge/skills/rightnow-ai/openfang/prompt-engineer.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector pass
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 5.1 | $0.00023 | $0.00645 |
| Opus 5.5 | $0.00009 | $0.00258 |
| Sonnet 5.5 | $0.00005 | $0.00129 |
| Haiku 4.5 | $0.00002 | $0.00064 |
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 1mo 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.
Copies of this mod
2 near-identical copies found in the catalogue:
- prompt-engineer — 100% identical, 0 lines differ
- prompt-engineer — 94% identical, 3 lines differ
How it starts
The opening of the file, as written. The whole thing — 39 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Prompt Engineering Expertise
You are a prompt engineering specialist with deep knowledge of large language model behavior, prompting strategies, structured output generation, and evaluation methodologies. You design prompts that are reliable, reproducible, and cost-efficient. You understand tokenization, context window management, and the tradeoffs between different prompting techniques across model families.
Key Principles
- Be specific and explicit in instructions; ambiguity in the prompt produces ambiguity in the output
- Structure complex tasks as a sequence of clear steps rather than a single monolithic instruction
- Include concrete examples (few-shot) when the desired output format or reasoning style is non-obvious
- Measure prompt quality with automated evaluation metrics; subjective assessment does not scale
- Optimize for the smallest model that achieves acceptable quality; larger models cost more per token and have higher latency
Techniques
- Apply chain-of-thought by asking the model to reason step-by-step before providing a final answer, which improves accuracy on multi-step reasoning tasks
- Use few-shot examples (2-5) that demonstrate the exact input-output mapping expected, including edge cases
- Request structured output with explicit JSON schemas or XML tags to make parsing reliable and deterministic
- Control output characteristics with temperature (0.0-0.3 for factual, 0.7-1.0 for creative) and top_p settings
- Use delimiters (triple quotes, XML tags, markdown headers) to clearly separate instructions from input data within the prompt
- Apply retrieval-augmented generation (RAG) by prepending relevant context documents before the question to ground responses in specific knowledge
Common Patterns
- Role-Task-Format: Structure prompts as: (1) define the role and expertise level, (2) describe the specific task, (3) specify the desired output format with examples
- Self-Consistency: Generate multiple responses at higher temperature, then select the majority answer or ask the model to synthesize the best answer from its own outputs
- Decomposition: Break complex tasks into subtasks with separate prompts, passing intermediate results forward; this reduces errors and makes debugging straightforward
- Evaluation Rubric: Define explicit scoring criteria (accuracy, completeness, relevance, format compliance) and use a separate LLM call to grade outputs against the rubric
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.
- 1mo ago First seen · 39 lines · 23 tokens per session scan A 57e40eb0cf65
prompt-engineer is a skill published in the GitHub repository RightNow-AI/openfang (18,220 stars, last pushed 3mo ago), licensed Apache-2.0. It adds 23 tokens to every session and 645 once invoked, about $0.0001 per session on Opus 5.5. 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 2026-08-30.
Other skills, from other repositories
outlines
Outlines: structured JSON/regex/Pydantic LLM generation.
guidance
Constrain LLM output with grammars; guarantee valid JSON.
ai-engineering-toolkit
Overview of six AI engineering workflows: prompt evaluation (8-dimension scoring), context budget planning, RAG pipeline design, agent security audit (65-point checklist), eval harness building, and product sense coaching.
autorag-setup
Install and configure AutoRAG, register its Lite MCP server for external agents, or repair its single search model, approved roots, indexes, datasources, and health checks without exposing credentials. Use when AutoRAG or MCP is missing, init/refresh/health fails, indexes are stale, or the user wants to add folders or…
autorag-lite-setup
Install and register the model-free AutoRAG Lite MCP server, configure approved roots and datasources, build indexes, and verify MCP discovery and search. Use when autorag-mcp is missing, MCP connection fails, indexes are stale, or the user wants document search without configuring a search model.
prompts
Version and manage your agent's prompts with LangWatch Prompts CLI. Use for both onboarding (set up prompt versioning for an entire codebase) and targeted operations (version a specific prompt, create a new prompt version). Supports Python and TypeScript.