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 stefanoskarakasis/Product-Marketing-Skills --skill writing-assistantgit clone --depth 1 https://github.com/stefanoskarakasis/Product-Marketing-SkillsWrote 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/stefanoskarakasis/product-marketing-skills/writing-assistant)<a href="https://agentmods.dev/skills/stefanoskarakasis/product-marketing-skills/writing-assistant"><img src="https://agentmods.dev/badge/skills/stefanoskarakasis/product-marketing-skills/writing-assistant/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/stefanoskarakasis/product-marketing-skills/writing-assistant"><img src="https://agentmods.dev/badge/skills/stefanoskarakasis/product-marketing-skills/writing-assistant.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector warn
SkillSpector: 2 findings, up to medium
These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →
- medium Excessive Agency · line 57 Skill enables autonomous high-impact decisions without human-in-the-loop verification. Critical operations (destructive commands, financial transactions, data deletion) should require explicit user confirmation.Fix: Add human-in-the-loop confirmation for destructive, irreversible, or high-impact operations. Never auto-execute commands that modify files, send data, or alter system state.
- medium Excessive Agency · line 66 Skill enables autonomous high-impact decisions without human-in-the-loop verification. Critical operations (destructive commands, financial transactions, data deletion) should require explicit user confirmation.Fix: Add human-in-the-loop confirmation for destructive, irreversible, or high-impact operations. Never auto-execute commands that modify files, send data, or alter system state.
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 | $0.00117 | $0.05823 |
| Opus 5.5 | $0.00047 | $0.02329 |
| Sonnet 5.5 | $0.00023 | $0.01165 |
| Haiku 4.5 | $0.00012 | $0.00582 |
Grade A, and why
writing-assistant 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 16d 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.
How it starts
The opening of the file, as written. The whole thing — 484 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Writing Assistant
You are a writing coach, sharp human editor, and messaging strategist for people working in B2B tech: PMs, engineers, designers, founders, marketers, and leadership teams. Preserve the user's point and personal voice while making the writing clearer, more direct, and more alive. Remove AI patterns without turning distinctive writing into generic polished prose.
Five jobs
Rewrite / Review (default). The user pastes existing text. Return a sendable rewrite plus only what genuinely blocks the outcome — no changelog of every edit.
Draft from scratch. The user asks to write something but gives no draft. Return a complete, sendable Version 1, then a short list of what needs filling in.
Behavioral Messaging Review. The user submits marketing copy or asks why it isn't landing/converting. This is a pressure-test against reader psychology, not a rewrite — it identifies missing behavioral leverage and prioritizes fixes.
Marketing content. The user wants a blog post, social post, newsletter, landing
page, press release, or case study. Gather the inputs, draft to the format's
structure, never invent proof. Format guides live in references/.
Audit. The user asks whether text reads as AI-written, or to scan it for AI patterns. Name the patterns, quote the lines, give short fixes. No rewrite.
Full mechanics for all five are in Workflow, at the bottom.
Route first
Decide the path before loading anything.
| The request is... | Path |
|---|---|
| A Slack message, async update, internal email, memo, PRD, deck, one-pager, cold email, or any text for one person or one team | Rewrite / Review or Draft, exactly as before. Do not run the marketing intake. |
| A blog post, social post, newsletter, landing page, press release, or case study | Marketing content |
| Existing copy plus "why isn't this converting?" | Behavioral Messaging Review |
| Existing copy plus "does this sound like AI?", "scan this", or "flag the AI patterns" | Audit |
What ships with it
22 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
- commands/cold-email.md 764 B
- commands/deck.md 768 B
- commands/email.md 682 B
- commands/homepage.md 1018 B
- commands/marketing-content.md 741 B
- commands/one-pager.md 731 B
- commands/README.md 786 B
- commands/slack.md 636 B
- evals/writing-assistant.eval.md 9.8 KB
- knowledge/craft/behavioral-science.md 4.9 KB
- knowledge/craft/patterns.md 1.4 KB
- knowledge/false-beliefs/catalog.md 1.1 KB
- knowledge/hypotheses/active.md 2.6 KB
- knowledge/INDEX.md 1.6 KB
- knowledge/sessions/log.md 773 B
- references/blog-post.md 1.7 KB
- references/case-study.md 1.8 KB
- references/landing-page.md 1.7 KB
- references/newsletter.md 1.2 KB
- references/press-release.md 1.9 KB
- references/seo-checklist.md 1.7 KB
- references/social-post.md 1.4 KB
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.
- 16d ago Changed · +2 lines d6bcd3d81521
- 17d ago Changed · +134 lines · +44 tokens per session 001f63515dee
- 1mo ago Changed · -2 lines 4244ce0c4277
- 1mo ago Changed · -79 lines · -89 tokens per session d3d9cfc0a53d
- 1mo ago First seen · 429 lines · 162 tokens per session scan A 32d1e2de2133
writing-assistant is a skill published in the GitHub repository stefanoskarakasis/Product-Marketing-Skills (8 stars, last pushed today), licensed MIT. It adds 117 tokens to every session and 5,823 once invoked, about $0.0005 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 2026-08-31.
Other skills, from other repositories
report
A way to export a chat card or reply as a standalone HTML report, meaning a file that can open in a browser without the chat application. It preserves the card template, including right-to-left Persian or left-to-right English layouts.
k8s-rightsize
Right-size Kubernetes CPU and memory requests from Prometheus usage (p95 CPU, p98 memory over 7 days), size the node count, tune KEDA autoscaling. Use when asked to rightsize workloads, cut node cost, or "how many nodes do we need".
owasp-security
Deep OWASP reference: Top 10 2025, ASVS 5.0, secure patterns, per-language quirks, LLM Top 10 and agentic AI security. Use for an in-depth security review, auth work, or hardening an LLM or agent app. For the everyday baseline use secure-coding.
fig
One self-contained HTML file holding a looping animated SVG, for ideas that move: flows, loops, retries, queues, fan-outs. Use when the user says "fig" or a diagram would be better animated.
brand
A project-specific visual identity for chat cards and saved reports, using the project's colors, logo, and fonts. It finds these details in the repository or asks the user for them, then stores the result in a committable `.readable/` folder.
workspace-rules
A set of guidelines for deciding which rules belong in a repository's workspace instructions and which should be enforced by its build or checks.