Zero of fourteen models named Google Postmaster Tools first on the direct prompt; one named Validity Everest. Google Postmaster Tools was named by thirteen of the fourteen models and Validity Everest by twelve and Google Postmaster Tools carries 34 labels and Validity Everest 32, so the shares are not directly comparable.
By Google, Mountain View, California, United States, founded 1998. Named in one category this edition.
Named in one category this edition.
Share is the count of first choices across the direct, paraphrase, budget and scale prompts over all fourteen models, for a mid-market B2B company; rank is within the category; every quote names the model and the prompt it came from. Both figures come from the email deliverability and testing tools page.
Across every category in the November 2026 Edition, Google Postmaster Tools and Validity Everest were named in the same answer thirty-four times, of the 84 answers naming Google Postmaster Tools and the 82 naming Validity Everest. In those answers Validity Everest took the first choice fourteen times and Google Postmaster Tools five.
| Model | DirectGP | ParaphraseGP | ComparativeGP | Budget-constrainedGP | Scale-constrainedGP | NegativeGP |
|---|---|---|---|---|---|---|
| Claude Haiku 4.5 | GP | GP | ||||
| GPT-5.4 mini | GP | |||||
| Gemini 3.5 Flash | GP | GP | ||||
| Perplexity Sonar | GP | GP | GP | GP | GP | |
| Grok 4.20 | GP | GP | GP | |||
| Mistral Small | GP | GP | ||||
| DeepSeek V4 Flash | GP | GP | GP | GP | ||
| Llama 4 Maverick | ||||||
| Qwen 3.7 Flash | GP | GP | ||||
| Kimi K2 | GP | |||||
| GLM 4.7 FlashX | GP | GP | ||||
| MiniMax M2.5 | GP | |||||
| GPT-6 Luna | GP | GP | GP | |||
| Muse Glimmer 30B | GP | GP | GP | GP |
Bold names in an answer are the products the judge labeled a first choice; a model naming several gives each of them that label. The full answer text for every row is in the record.
Every negative label with a quote, up to three, then the highest-weighted positives, up to three. Five of six in this category shown.
“tools such as Google Postmaster Tools are valuable, but Gmail data can be delayed or unavailable at low volume” Perplexity Sonar · negative prompt · soft negative
“valuable if you send enough to Gmail to get data, but it's not a full inbox placement tester” GPT-5.4 mini · comparative prompt · soft negative
“For maximum budget efficiency, start with Google Postmaster Tools and MXToolbox, which are both free” Claude Haiku 4.5 · budget prompt · first choice
“Best first step for monitoring Gmail delivery, spam reports, authentication, and delivery errors.” GPT-6 Luna · budget prompt · first choice
“If you are starting out, begin with Google Postmaster Tools (free, essential for Gmail data)” Qwen 3.7 Flash · comparative prompt · first choice
Every negative label with a quote, up to three, then the highest-weighted positives, up to three. Six of eight in this category shown.
“Unnecessary enterprise tools (Validity Everest, etc.) unless you're at scale.” GLM 4.7 FlashX · budget prompt · hard negative
“High price tag (typically starting at $5,000–$15,000+/year) and demo-first sales cycles, which can be overkill for mid-sized teams.” Gemini 3.5 Flash · direct prompt · soft negative
“rather than paying for an expensive all-in-one suite (like Validity Everest or Inbox Monster, which can cost hundreds per month)” Gemini 3.5 Flash · budget prompt · soft negative
“Validity Everest and Allegrow are the top choices due to their scalability, B2B focus, and comprehensive feature sets” Mistral Small · direct prompt · first choice
“For marketers: Start with GlockApps or Validity Everest for deliverability” Mistral Small · comparative prompt · first choice
“Use a combination: GlockApps or Validity (for placement testing)” Grok 4.20 · negative prompt · first choice
Comparisons are drawn for the top eight products in each category, each against each. The output is the models' output; nothing here is a recommendation by the index.