AWS Threat Composer vs TSpec

AWS Threat Composer is a threat-modeling project for identifying security issues and developing ways to address them. Its structured threat grammar offers adaptive suggestions for composing threat statements. Models can include architecture and data-flow diagrams, tracked assumptions, links between threats and mitigations, and an insights dashboard with quality metrics and improvement suggestions. Users can manage multiple models and export them as JSON, Markdown, DOCX, or PDF. The web application stores data in the browser, supports import and export, and is available as a hosted demo or as a static site deployed in an AWS account. The VS Code extension in AWS Toolkit edits .tc.json files, works offline, and stores data locally. A browser extension displays threat model files on GitHub, GitLab, Bitbucket, and Amazon CodeCatalyst; it is read-only and requires internet access for web-hosted files. The AI-assisted CLI and MCP server can analyze source code to create starter models, but the tools are experimental. They use AWS Bedrock, and inference costs apply.

TSpec has no write-up on Specifiction yet; its figures are above.