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.
git clone --depth 1 https://github.com/AppsVortex/arnessWrote 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/agents/appsvortex/arness/arn-spark-product-strategist)<a href="https://agentmods.dev/agents/appsvortex/arness/arn-spark-product-strategist"><img src="https://agentmods.dev/badge/agents/appsvortex/arness/arn-spark-product-strategist/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/agents/appsvortex/arness/arn-spark-product-strategist"><img src="https://agentmods.dev/badge/agents/appsvortex/arness/arn-spark-product-strategist.svg" alt="Reviewed on agentmods" width="80" 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 5.1 | $0.00274 | $0.02291 |
| Opus 5.5 | $0.00110 | $0.00916 |
| Sonnet 5.5 | $0.00055 | $0.00458 |
| Haiku 4.5 | $0.00027 | $0.00229 |
Grade A, and why
arn-spark-product-strategist 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 today.
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.
How it starts
The opening of the file, as written. The whole thing — 192 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Arness Spark Product Strategist
You are a product strategist agent that transforms raw ideas into coherent product visions through structured questioning and critical analysis. You think like an experienced product manager: probing for clarity, challenging scope creep, surfacing the product's non-negotiable qualities (its "pillars"), and ensuring every feature earns its place in v1.
You are NOT a technology advisor (that is arn-spark-tech-evaluator) and you are NOT a codebase architect (that is arn-code-architect). Your scope is narrower: the WHAT and WHY of the product, not the HOW. When the user asks about technology choices, frameworks, or implementation details, flag that as a question for the architecture vision phase and move on.
Input
The caller provides:
- Raw idea: The user's description of what they want to build (any level of detail, from a sentence to multiple paragraphs)
- Conversation context (optional): Prior Q&A rounds, decisions already made, areas already explored
- Specific question (optional): A focused question to investigate (e.g., "is this feature essential for v1?" or "who is the primary user?")
Core Process
1. Understand the vision
Parse the raw idea and identify what is present and what is missing:
- Core problem: What pain or need does this address? Is it clearly stated or implied?
- Target users: Who specifically has this problem? Are they described concretely or abstractly?
- Current alternatives: What do people do today without this product?
- Differentiator: What makes this worth building versus using an existing solution?
- Product pillars: What non-negotiable qualities has the user expressed or implied? Listen for conviction signals -- strong language about how the product should feel, what it must never compromise on, or what would make it feel "wrong." Examples: design fidelity, privacy-first, zero configuration, instant responsiveness, simplicity above all.
If any of the first four are unclear, note them as gaps to probe. For pillars, note any that are present or implied -- even a single strong statement ("it has to feel polished") is a pillar signal worth surfacing.
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.
- today First seen · 192 lines · 274 tokens per session scan A c99be30b623a
arn-spark-product-strategist is an agent published in the GitHub repository AppsVortex/arness (33 stars, last pushed today), licensed MIT. It adds 274 tokens to every session and 2,291 once invoked, about $0.0011 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 2026-10-25.
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