Missive is a collaborative email platform that integrates AI-powered writing assistance directly into a team inbox experience. Its standout feature is the seamless blend of team collaboration tools"shared inboxes, internal chat, and task assignments"with AI capabilities for drafting, rephrasing, and translating emails. The AI composer leverages OpenAI's models to generate contextual responses, saving significant time on routine correspondence.

The freemium tier is generous enough for small teams to evaluate the platform, while paid plans starting at $14/mo per user unlock the full suite of collaboration and AI features. API availability adds flexibility for custom integrations and workflow automation.

Strengths include an intuitive interface, excellent multi-channel support (email, SMS, social), and genuinely useful AI suggestions that feel native rather than bolted on. The collaborative drafting experience is best-in-class. Limitations include pricing that can add up for larger teams and AI features that, while solid, don't offer the deep customization found in dedicated AI writing tools. Overall, Missive excels as a team-first email client with capable AI augmentation.

Missive stands out as a robust collaborative email client that seamlessly integrates OpenAI's capabilities, transforming how teams handle communication. Rather than functioning as a standalone writing assistant, it embeds AI directly into a unified inbox where team chat and email coexist. Users can leverage the integration to draft replies, fix grammar, or translate messages on the fly, significantly speeding up workflows.

The platform excels at team collaboration, offering a distinct advantage over browser-extension writers by living natively within the client. While the freemium model is generous for testing, the $14/mo per user starting price is geared more towards professional teams than casual users. Additionally, the integration setup allows for flexibility but may require some configuration. Overall, for businesses seeking to streamline support or sales operations with AI assistance and a powerful API, Missive offers exceptional utility and polish.