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email-systems

You are an email systems engineer who has maintained 99.9% deliverability across millions of emails. You've debugged SPF/DKIM/DMARC, dealt with blacklists, and optimized for inbox placement. You know that email is the highest ROI channel when done right, and a spam folder nightmare when done wrong.

33

Quality

29%

Does it follow best practices?

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SecuritybySnyk

Passed

No findings from the security scan

Fix and improve this skill with Tessl

tessl review fix ./skills/email-systems/SKILL.md
SKILL.md
Quality
Evals
Security

Quality

Content

22%Scale 1-5

Reviews the quality of instructions and guidance provided to agents. Good implementation is clear, handles edge cases, and produces reliable results.

This skill is essentially a skeleton or outline with no actionable content. It names important email deliverability concepts and patterns but provides zero executable guidance—no DNS record examples, no code for queue implementation, no DKIM configuration, no bounce handling logic. The sharp edges table is particularly problematic as it identifies critical issues but leaves the solution column as empty comments.

Suggestions

Add concrete, executable examples for each pattern—e.g., actual SPF/DKIM/DMARC DNS record formats, a transactional email queue implementation with retry logic, and bounce webhook processing code.

Fill in the Sharp Edges 'Solution' column with actual solutions: real DNS record examples, IP warm-up schedules with specific daily volume numbers, and unsubscribe header implementation.

Add at least one complete workflow with sequenced steps and validation—e.g., 'Setting up email deliverability: 1. Configure SPF record → 2. Set up DKIM signing → 3. Validate with `dig` commands → 4. Configure DMARC → 5. Test with mail-tester.com'.

Remove the duplicated persona description from the body and the boilerplate 'When to Use' section to improve conciseness.

DimensionReasoningScore

Conciseness

The skill repeats the persona description from the frontmatter in the body, and includes some filler ('You treat deliverability as infrastructure, not an afterthought'). The sharp edges table is reasonably compact but the 'Solution' column contains only comments with no actual solutions. The 'When to Use' section is boilerplate filler.

3 / 5

Actionability

The skill provides no concrete code, commands, configurations, or executable guidance. Patterns are named but not implemented. The sharp edges table lists issues but the 'Solution' column contains only placeholder comments (e.g., '# Required DNS records:') with no actual DNS records, configurations, or code examples.

1 / 5

Workflow Clarity

There are no sequenced steps, no workflows, no validation checkpoints. The patterns section names workflows (email queue, event tracking, template versioning) but provides zero implementation detail or step sequences. There is no guidance on how to actually perform any operation.

1 / 5

Progressive Disclosure

The content is organized into logical sections (Patterns, Anti-Patterns, Sharp Edges) which provides some structure. However, there are no references to external files for detailed implementations, and the content that exists is too thin to warrant splitting. The structure is present but the sections are hollow.

3 / 5

Total

8

/

20

Passed

Description

36%Scale 1-5

Based on the skill's description, can an agent find and select it at the right time? Clear, specific descriptions lead to better discovery.

This description is written as a first/second-person persona backstory ('You are an email systems engineer who has maintained...') rather than a functional skill description. It fails to clearly state what actions the skill performs and provides no 'when to use' guidance. The technical terms provide some trigger value, but the overall format is poorly suited for skill selection among many options.

Suggestions

Rewrite in third person with concrete action verbs: e.g., 'Diagnoses email deliverability issues, configures SPF/DKIM/DMARC records, troubleshoots blacklist problems, and optimizes inbox placement rates.'

Add an explicit 'Use when...' clause with natural trigger phrases: e.g., 'Use when the user mentions email going to spam, deliverability problems, DNS authentication records, bounce rates, or email reputation issues.'

Remove the persona framing ('You are an email systems engineer...') and replace with a capability-focused description that helps Claude distinguish this skill from general email or DNS skills.

DimensionReasoningScore

Specificity

Names the domain (email deliverability) and mentions SPF/DKIM/DMARC, blacklists, and inbox placement, but these are framed as past experience claims rather than concrete actions the skill performs. No actionable verbs like 'configures', 'diagnoses', or 'generates' are used.

2 / 5

Completeness

The 'what' is vaguely implied through experience claims rather than explicitly stated capabilities. There is no 'when' clause or any guidance on when Claude should select this skill. The description reads as a persona backstory, not a functional skill description.

2 / 5

Trigger Term Quality

Includes relevant technical terms like SPF, DKIM, DMARC, blacklists, deliverability, and inbox placement that users might mention. However, it misses common natural phrases like 'email going to spam', 'DNS records', 'email authentication', or 'bounce rate'.

3 / 5

Distinctiveness Conflict Risk

The email deliverability niche is somewhat specific, but the description's vague framing as expertise rather than concrete actions means it could overlap with general email marketing or DNS configuration skills.

3 / 5

Total

10

/

20

Passed

Validation

90%

Checks the skill against the spec for correct structure and formatting. All validation checks must pass before discovery and implementation can be scored.

Validation10 / 11 Passed

Validation for skill structure

CriteriaDescriptionResult

frontmatter_unknown_keys

Unknown frontmatter key(s) found; consider removing or moving to metadata

Warning

Total

10

/

11

Passed

Repository
administrakt0r/AI-Agents-Safe-Coding-Skills
Reviewed

Table of Contents

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