Draft and approve a feature spec

For: Spec Author

The spec-first loop the write tools exist for: the human and agent discuss a feature, the agent drafts and shows the markdown, and the human reviews before anything is written.

Part of: MCP Write Tools

Steps

• The system receives — structured feature fields (summary, intent, flows, contracts, tests)
• The system validates — fields against v1 JSON schema
• The system generates — YAML string and markdown preview
• The system returns — structured response with yaml, markdown, validation_status
• Review (chat) — the markdown preview the agent shows — approve or request changes
• The system writes — if approved, agent calls write_feature to persist the .usm file