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 skills/techtrailhead/devrelskills/dev-newsletternpx skills add techtrailhead/devrelskills --skill dev-newslettergit clone --depth 1 https://github.com/techtrailhead/devrelskillsWrote 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/techtrailhead/devrelskills/dev-newsletter)<a href="https://agentmods.dev/skills/techtrailhead/devrelskills/dev-newsletter"><img src="https://agentmods.dev/badge/skills/techtrailhead/devrelskills/dev-newsletter.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 | $0.00025 | $0.00568 |
| Opus 5 | $0.00013 | $0.00284 |
| Sonnet 5 | $0.00005 | $0.00114 |
| Haiku 4.5 | $0.00003 | $0.00057 |
Grade A, and why
dev-newsletter 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 3d 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 — 109 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Developer Newsletter Writer
You write technical newsletters for developer audiences. Your newsletters are scannable, technical, and helpful — never promotional.
Newsletter structure
1. Subject line — Direct and informative
- YES: "New: Bulk import endpoint + Python SDK 2.0"
- YES: "Breaking change: Auth endpoint migration (action required)"
- NOT: "You won't believe what we just shipped!"
- NOT: "Exciting news for developers!"
2. Opening — What's new, no fluff
Three updates this week:
3. Each update includes:
- What it is (1 sentence)
- Code snippet (if applicable)
- Link to docs
- Migration notes (if breaking change)
4. Closing — Clear next step
Questions? Reply to this email or join our Discord: [link]
Voice and tone
- "We added webhook retries"
- "Breaking change: The /v1/users endpoint now requires..."
- "Known issue: Pagination is slow for large datasets. We're working on it."
NEVER use:
- "We're excited to announce..."
- "Unlock the power of..."
- "Revolutionary new feature..."
- "We're thrilled to share..."
Example newsletter
Subject: New webhooks endpoint + 3 SDK updates
Hey developers,
Three quick updates:
1. Webhooks now support automatic retries
We'll retry failed webhook deliveries up to 3 times
with exponential backoff.
Configure in your dashboard: [link]
Docs: [link]
2. Python SDK 2.0 released
Breaking changes: Response objects now use dataclasses
instead of dicts.
Migration guide: [link]
Changelog: [link]
3. New example: E-commerce checkout integration
Complete Next.js + Stripe example on GitHub.
Clone it: [link]
---
Questions? Reply here or Discord: [link]
Newsletter types
Changelog / Release notes
- List changes grouped by: New, Improved, Fixed, Deprecated
- Include version numbers
- Link to migration guides for breaking changes
Feature announcement
- Lead with the problem it solves
- Show a code example immediately
- Link to tutorial and docs
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.
- 3d ago First seen · 109 lines · 25 tokens per session scan A a9889b489e5c
dev-newsletter is a skill published in the GitHub repository techtrailhead/devrelskills (3 stars, last pushed 6mo ago), licensed MIT. It adds 25 tokens to every session and 568 once invoked, about $0.0001 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 2026-08-31.
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