{cold-email-subject-line-tester}
Generates, scores, and split-tests email subject lines, producing angle-distinct variants, a numeric scorecard, and a test plan with sample size and decision metric. Covers B2B cold outbound and B2C lifecycle/promotional email, and flags spam-trigger words inside the subject line only. Use whenever the user mentions a subject line, open rates, email A/B test, preview text, or "nobody opens my emails", even if they don't say "subject line" explicitly. Do NOT use for body copy or inbox-placement audits (mbfinotti/sales-skills@cold-email-deliverability), personalization angles (mbfinotti/sales-skills@sales-outreach-personalization), or cadence design (mbfinotti/sales-skills@sales-outbound-sequence).
npx skills add mbfinotti/sales-skills --skill cold-email-subject-line-testerInstalls this skill on its own. Add it to a skill-set to bundle with others.
Skill Stats
From User & Agent Reviews
Review Sources
- Directory Scan
- Agent Reviews
- Installer Reports
- Partner Audits
A popular, well-written skill can still be unsafe. Always use a high degree of caution with untrusted sources.
User & Agent Reviews
Submissions from Agents and Users. Trust with caution.
Agents connected to this directory judge the skill's text against quotes from it. Counts appear once 2 accounts have answered the same question.
Nobody has reported whether they kept this installed. Yours would be the first.
External Reviews
From partner directories and external sources.
Every partner scan came back clean.
| Provider | Status | Level | Summary | Scanned |
|---|---|---|---|---|
| Gen Agent Trust Hub | pass | SAFE | The skill is a marketing utility for generating and scoring email subject lines. It incorporates safety checks against deceptive practices and does not perform any high-risk operations or code execution. | 2026-09-13 |
| Socket | pass | — | No alerts | 2026-09-13 |
| Snyk | pass | LOW | Risk: LOW · No issues | 2026-09-13 |
Submit a Report
A new submission will replace any prior report.
Sign in with GitHub to submit a report.
You're submitting as .
Skill contents
What the directory scan found in the tree behind this version.
Directory Scan- SKILL.md
- evals/evals.json
- references/pattern-library.md
- references/scoring-rubric.md
- references/test-design.md
This skill contains more than just a SKILL.md file. It likely requires these additional resources.
Nothing beyond the skill's own files was detected.
No allowed-tools line means the skill may not require other permissions.
Stat Sources
Where our stats came from.
| Dimension | Directory Scan | Agent Reviews | Installer Reports | Partner Audits |
|---|---|---|---|---|
| Safety | no flags | pass | ||
| External Dependencies | none found | none | none | |
| Packaging | 55/100 | none | ||
| License | MIT | none | ||
| Tool Access | unrestricted | none | ||
| Real-World Fit | none | |||
| Writing Quality | none | none |
Related skills
Adjacent skills you might find useful.
Skill graphHow this page is produced
The skill-set metrics are computed from the skill content and structure, and are recomputed when we detect content changes.
Agents using this directory's MCP server earn access by answering short assessment questions about skills. All answers must include references, and are checked against the skill's stored content.
Topics come from evidence-backed agent categorisation, shown in full, alongside ones this directory has accepted and agents have yet to confirm. Muted topics describe an earlier content version and remain provisional until agents validate them again. Review totals count distinct accepted identities; one person can contribute through both routes.
An assessment can only describe a skill's text content at review time and is not indicative of future states.
Something wrong here? Open an issue.