email-best-practices

Use when building email features, emails going to spam, high bounce rates, setting up SPF/DKIM/DMARC authentication, implementing email capture, ensuring compliance (CAN-SPAM, GDPR, CASL), handling webhooks, retry logic, making emails accessible (alt text, headings, contrast, screen readers), or deciding transactional vs marketing.

Quality

89%

Does it follow best practices?

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Adds up to 20 points to the overall score

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Securityby

Passed

No findings from the security scan

Quality

Content

78%Weight 40%Scale 1-5

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

The body is a well-structured hub: concise, navigable, with all referenced files present and one level deep. Its main weakness is actionability, since executable code/commands are deferred entirely to references rather than including even a minimal inline example.

Suggestions

Add a small inline executable snippet (e.g. a minimal authenticated send or a SPF/DKIM/DMARC DNS record example) so the SKILL.md itself offers at least one copy-paste-ready action.

For the production-sending path, include an explicit verification checkpoint (e.g. 'verify DNS records resolve before sending the first email') so the workflow has a validation step rather than only reading order.

Annotate the Quick Reference table with a one-word scope hint per row (setup vs. build vs. operate) to speed routing when multiple needs overlap.

Dimension	Reasoning	Score
Conciseness	The body is lean — an architecture diagram, a dense Quick Reference table, and brief scenario paths — with no padding explaining what email is or how libraries work; every section earns its tokens.	5 / 5
Actionability	It gives concrete routing decisions (specific reference files for specific needs and ordered scenario paths) but contains no executable code or commands itself — the actionable execution lives entirely in the referenced files, which is incomplete guidance at the SKILL.md level.	3 / 5
Workflow Clarity	Start Here provides clear ordered sequences (e.g. 'Email Capture → Compliance → Marketing Emails'; 'Sending Reliability → Webhooks & Events → List Management'), but these are reading-order paths without explicit validation checkpoints.	4 / 5
Progressive Disclosure	The SKILL.md is a clear overview with well-signaled, one-level-deep references — all 11 referenced files exist and are surfaced via both a Quick Reference table and Start Here routing — with details appropriately split into references.	5 / 5
	Total	17 / 20 Passed

Description

100%Weight 40%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.

The description is strong across all dimensions: it uses an explicit 'Use when' trigger, names concrete actions and protocols, and stays clearly within an email-specific niche. It avoids first/second-person voice and vague filler.

Dimension	Reasoning	Score
Specificity	The description lists multiple specific concrete actions — 'setting up SPF/DKIM/DMARC authentication', 'implementing email capture', 'handling webhooks, retry logic', 'making emails accessible (alt text, headings, contrast, screen readers)' — giving comprehensive coverage rather than vague abstractions.	5 / 5
Completeness	An explicit 'Use when' clause supplies concrete trigger conditions, and the body lists the concrete capabilities (authentication, capture, compliance, webhooks, accessibility, transactional vs marketing), clearly answering both what and when.	5 / 5
Trigger Term Quality	It uses natural phrases users actually say — 'emails going to spam', 'high bounce rates', 'SPF/DKIM/DMARC', 'CAN-SPAM, GDPR, CASL', 'screen readers', 'alt text' — with synonyms and concrete protocol/regulation names for comprehensive keyword coverage.	5 / 5
Distinctiveness Conflict Risk	It carves a clear email-specific niche with distinct triggers (SPF/DKIM/DMARC, bounce rates, CAN-SPAM/GDPR/CASL) that are unlikely to match a non-email skill, keeping conflict risk minimal.	5 / 5
	Total	20 / 20 Passed

Validation

93%

Warnings & errors only

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

Validation — 15 / 16 Passed

Validation for skill structure

Criteria	Description	Result
metadata_field	'metadata' should map string keys to string values	Warning

	Total	15 / 16 Passed

Repository: resend/resend-skills
Path: skills/email-best-practices/SKILL.md
Commit: 865a368

Reviewed: 1 day ago

Table of Contents

Discovery Implementation Validation

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