Postbox

Postbox is a structured data collection platform designed for both agents and humans, focusing on providing form endpoints with advanced processing capabilities. It addresses the common challenge of ensuring reliable, validated, and organized data collection for web forms and automated agents. Users define a schema for each form, which Postbox enforces at the endpoint, guaranteeing that submissions are validated according to types, required fields, patterns, and ranges. Invalid data is rejected with structured per-field error messages, preventing bad data from entering the system.

The platform incorporates spam filtering using built-in heuristics, with an option to enable AI-based spam detection that understands the intent of each form, filtering out unwanted or irrelevant submissions. Submissions in any language are automatically detected and translated, with both the original and translated versions retained in the inbox. Postbox also drafts replies to submissions by referencing a connected knowledge base, and can send these replies automatically when configured to do so, streamlining routine interactions such as answering frequently asked questions.

Postbox integrates with agents through the Postbox Skill, which can be installed into a codebase to allow coding agents to create and manage forms, wire endpoints, and generate UI components. It also connects with MCP-aware clients, enabling users to create forms and manage submissions directly within chat interfaces. Additionally, a dashboard is available for manual management and review. The system processes each submission through a configurable pipeline that includes validation, spam check, translation, reply drafting, and notification steps, with each step adjustable per form.

The platform is suitable for a range of use cases, including marketing forms (such as waitlists and lead capture), support (contact forms, bug reports, feature requests), and operational workflows (like vendor onboarding). Postbox offers a free tier to help users get started with its structured data collection capabilities.