Cold Email: test results
Tested 2026-09-30, skill version 1.0.0 at the time of loading this page. We run every skill on a strong and a weak model before it is listed, and publish both verdicts, including where the weak one fails.
Verdicts
- Date
- 2026-09-30
- Strong · claude-sonnet-5-5 (Claude Code alias "sonnet")
- 6 of 6 cases pass (en, bg, de, es, ru, thin brief). Right language, formal address, 60-110 words, one ask, easy exit, and no invented facts: with almost no brief it wrote a role-based reason and said it was writing without prior contact.
- Weak · claude-haiku-4-5-20251001 (Claude Code alias "haiku")
- 6 of 6 pass the mechanical checks, but reading the texts shows real flaws: invents claims not in the brief ("most bakery owners I work with", "no massive minimums", "no surprise bills"), flatters ("great milestone"), ignores the formal-address rule in de/es/bg greetings (Hallo, Hola Laura, first-name only), leaves the Russian email without a greeting and with an English "Subject:" label, and on the thin brief does not say it is a first contact. Review its drafts before use.
Note
One run per model and case (run 2 of 2; run 1 failed only because of a mistaken length check in our own cases, fixed). Checks are mechanical (language, kept names, banned phrases, a subject line, at most 139 words); they cannot detect invented claims, which we read by hand.
What was not measured
- Models other than the two named above were not run.
- Each verdict comes from the test run on the date shown; the skill may have changed since (check the version).
- Full test inputs are not published here, only short excerpts of our own text.
- Results on your own texts, languages and domains can differ.