Prompt versioning and managementA/B testing frameworkCustom evaluation metricsModel comparison across providersPerformance benchmarkingTeam collaboration workspaceAPI for integration
Features
AI email writing and reply generation using context from received emailsWorks in any text field across any website via browser extensionSupport for 20+ languagesGrammar and tone correctionContext-aware response generationOne-click reply drafting in GmailCustom instructions for personalized writing style
Pricing Tiers
Pricing Tiers—
Pricing Tiers
Free$0/mo/monthly
Limited AI generations per week
Premium/monthly
Unlimited generations, priority access
Integrations
Integrations
OpenAIAnthropicCoherecustom APIs
Integrations
GmailGoogle DocsLinkedInTwitter/XFacebookAny web-based text field (via Chrome extension)
Platforms
Platforms
webapi
Platforms
chrome-extension
Pros
Pros
Purpose-built for LLM evaluation and iteration
Custom evaluation metrics for domain-specific quality assessment
Version control and A/B testing for prompts and models
Collaborative interface for cross-functional teams
API-first approach enables integration into existing workflows
Pros
Works across any website text field, not limited to a single platform
Deep Gmail integration reads email context to generate accurate replies
Supports 20+ languages for multilingual users
No need to leave the current tab — drafts appear inline
Free tier available for light use without a credit card
Cons
Cons
Requires some technical setup to fully utilize
Learning curve for creating custom evaluation metrics
Limited to LLM applications, not broader ML use cases
Community and ecosystem still developing
Pricing information sparse for smaller teams
Cons
Limited to Chrome (and Chromium-based) browsers — no Firefox or Safari support
No standalone web app or mobile app; entirely extension-dependent
Free tier has generation limits that can be restrictive for daily heavy use
Less suitable for long-form content like blog posts or reports
Output quality depends heavily on the prompt/context provided by the user