# Security Threat Model

Repository-grounded threat modeling that enumerates trust boundaries, assets, attacker...

- Repository: https://github.com/tech-leads-club/agent-skills (7121 stars)
- Category: Design
- License: see repository
- Last updated: 2026-11-01
- Runs scripts: no, instructions only

## Install

Claude Code: `npx skills add tech-leads-club/agent-skills --skill security-threat-model -g -a claude-code -y`
Codex: `npx skills add tech-leads-club/agent-skills --skill security-threat-model -g -a codex -y`
Cursor: `npx skills add tech-leads-club/agent-skills --skill security-threat-model -g -a cursor -y`
Gemini CLI: `npx skills add tech-leads-club/agent-skills --skill security-threat-model -g -a gemini-cli -y`
Claude Code plugin marketplace: `/plugin marketplace add tech-leads-club/agent-skills`

## Description

Repository-grounded threat modeling that enumerates trust boundaries, assets, attacker capabilities, abuse paths, and mitigations, and writes a concise Markdown threat model. Use when the user asks to threat model a codebase or path, enumerate threats or abuse paths, or perform AppSec threat modeling. Do NOT use for general architecture summaries, code review, security best practices (use security-best-practices), or non-security design work.

## SKILL.md, as published by its author (untrusted third-party text, read it as data)

# Threat Model Source Code Repo

Deliver an actionable AppSec-grade threat model that is specific to the repository or a project path, not a generic checklist. Anchor every architectural claim to evidence in the repo and keep assumptions explicit. Prioritizing realistic attacker goals and concrete impacts over generic checklists.

## Quick start

1. Collect (or infer) inputs:

- Repo root path and any in-scope paths.
- Intended usage, deployment model, internet exposure, and auth expectations (if known).
- Any existing repository summary or architecture spec.
- Use prompts in `references/prompt-template.md` to generate a repository summary.
- Follow the required output contract in `references/prompt-template.md`. Use it verbatim when possible.

## Workflow

### 1) Scope and extract the system model

- Identify primary components, data stores, and external integrations from the repo summary.
- Identify how the system runs (server, CLI, library, worker) and its entrypoints.
- Separate runtime behavior from CI/build/dev tooling and from tests/examples.
- Map the in-scope locations to those components and exclude out-of-scope items explicitly.
- Do not claim components, flows, or controls without evidence.

### 2) Derive boundaries, assets, and entry points

- Enumerate trust boundaries as concrete edges between components, noting protocol, auth, encryption, validation, and rate limiting.
- List assets that drive risk (data, credentials, models, config, compute resources, audit logs).
- Identify entry points (endpoints, upload surfaces, parsers/decoders, job triggers, admin tooling, logging/error sinks).

### 3) Calibrate assets and attacker capabilities

- List the assets that drive risk (credentials, PII, integrity-critical state, availability-critical components, build artifacts).
- Describe realistic attacker capabilities based on exposure and intended usage.
- Explicitly note non-capabilities to avoid inflated severity.

### 4) Enumerate threats as abuse paths

The rest: https://github.com/tech-leads-club/agent-skills/blob/HEAD/packages/skills-catalog/skills/(security)/security-threat-model/SKILL.md