Threat Model Analyst

GitHubOfficialFirst committed by cheguvDistributed by GitHub

Skill
Review and audit
Security
MIT
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From the author

Full STRIDE-A threat model analysis and incremental update skill for repositories and systems. Supports two modes: (1) Single analysis — full STRIDE-A threat model of a repository, producing architecture overviews, DFD diagrams, STRIDE-A analysis, prioritized findings, and executive assessments. (2) Incremental analysis — takes a previous threat model report as baseline, compares the codebase at the latest (or a given commit), and produces an updated report with change tracking (new, resolved, still-present threats), STRIDE heatmap, findings diff, and an embedded HTML comparison. Only activate when the user explicitly requests a threat model analysis, incremental update, or invokes /threat-model-analyst directly.

— the description by cheguv

AutoGineer summary

Written by AutoGineer from the skill’s own files, not by the author

Threat Model Analyst is a specialized agent skill designed to perform rigorous security audits using the STRIDE-A (STRIDE + Abuse) methodology. It operates in two primary modes: a full initial analysis for new systems and an incremental mode for tracking security posture changes over time. The skill enforces strict architectural modeling rules, particularly regarding Kubernetes sidecar co-location, and provides structured, evidence-based reporting including DFD diagrams, prioritized findings, and executive assessments.

What it does

Performs full STRIDE-A threat modeling including DFD generation and architectural risk assessment.
Executes incremental analysis to track new, resolved, and persistent threats between code versions.
Identifies security gaps by verifying infrastructure components and platform defaults before flagging.
Generates standardized security reports including architecture overviews and prioritized findings.
Maps security findings to industry standards like CVSS 4.0, CWE, and OWASP.
Enforces consistent diagramming conventions for complex system architectures.

When to use it

When you need a comprehensive security audit of a new repository or system architecture.
When you need to update an existing threat model to reflect recent code changes.
When you need to compare the security posture between two specific commits or report versions.
When you need to identify trust boundary violations or architectural security risks.

Advantages

Reduces false positives by requiring evidence-based verification of security controls.
Maintains continuity in security documentation through incremental change tracking.
Ensures architectural diagrams accurately reflect Kubernetes pod-level sidecar co-location.
Provides actionable, prioritized security findings mapped to recognized industry frameworks.

Usage examples

“Perform a full STRIDE-A threat model analysis on this repository.”: The agent will analyze the codebase, generate architecture diagrams, identify threats, and produce a comprehensive security report.
“Run an incremental threat model analysis using the report from last week as a baseline.”: The agent will compare the current codebase against the previous report to identify new, fixed, or remaining security threats.

Install

Download the skill as a ZIP:
https://mp-staging.autogineer.com/agent-skills/github/threat-model-analyst/download

Unzip it into the cross-client skills folder of your project:

mkdir -p .agents/skills && unzip threat-model-analyst.zip -d .agents/skills

Documentation by cheguv

Threat Model Analyst

You are an expert Threat Model Analyst. You perform security audits using STRIDE-A (STRIDE + Abuse) threat modeling, Zero Trust principles, and defense-in-depth analysis. You flag secrets, insecure boundaries, and architectural risks.

Getting Started

FIRST — Determine which mode to use based on the user's request:

Incremental Mode (Preferred for Follow-Up Analyses)

If the user's request mentions updating, refreshing, or re-running a threat model AND a prior report folder exists:

Action words: "update", "refresh", "re-run", "incremental", "what changed", "since last analysis"
AND a baseline report folder is identified (either explicitly named or auto-detected as the most recent threat-model-* folder with a threat-inventory.json)
OR the user explicitly provides a baseline report folder + a target commit/HEAD

Examples that trigger incremental mode:

"Update the threat model using threat-model-20260309-174425 as the baseline"
"Run an incremental threat model analysis"
"Refresh the threat model for the latest commit"
"What changed security-wise since the last threat model?"

→ Read incremental-orchestrator.md and follow the incremental workflow. The incremental orchestrator inherits the old report's structure, verifies each item against current code, discovers new items, and produces a standalone report with embedded comparison.

Comparing Commits or Reports

If the user asks to compare two commits or two reports, use incremental mode with the older report as the baseline. → Read incremental-orchestrator.md and follow the incremental workflow.

Single Analysis Mode

For all other requests (analyze a repo, generate a threat model, perform STRIDE analysis):

→ Read orchestrator.md — it contains the complete 10-step workflow, 34 mandatory rules, tool usage instructions, sub-agent governance rules, and the verification process. Do not skip this step.

Reference Files

Load the relevant file when performing each task:

File	Use When	Content
Orchestrator	Always — read first	Complete 10-step workflow, 34 mandatory rules, sub-agent governance, tool usage, verification process
Incremental Orchestrator	Incremental/update analyses	Complete incremental workflow: load old skeleton, change detection, generate report with status annotations, HTML comparison
Analysis Principles	Analyzing code for security issues	Verify-before-flagging rules, security infrastructure inventory, OWASP Top 10:2025, platform defaults, exploitability tiers, severity standards
Diagram Conventions	Creating ANY Mermaid diagram	Color palette, shapes, sidecar co-location rules, pre-render checklist, DFD vs architecture styles, sequence diagram styles
Output Formats	Writing ANY output file	Templates for 0.1-architecture.md, 1-threatmodel.md, 2-stride-analysis.md, 3-findings.md, 0-assessment.md, common mistakes checklist
Skeletons	Before writing EACH output file	8 verbatim fill-in skeletons (`skeleton-*.md`) — read the relevant skeleton, copy VERBATIM, fill `[FILL]` placeholders. One skeleton per output file. Loaded on-demand to minimize context usage.
Verification Checklist	Final verification pass + inline quick-checks	All quality gates: inline quick-checks (run after each file write), per-file structural, diagram rendering, cross-file consistency, evidence quality, JSON schema — designed for sub-agent delegation
TMT Element Taxonomy	Identifying DFD elements from code	Complete TMT-compatible element type taxonomy, trust boundary detection, data flow patterns, code analysis checklist

When to Activate

Incremental Mode (read incremental-orchestrator.md for workflow):

Update or refresh an existing threat model analysis
Generate a new analysis that builds on a prior report's structure
Track what threats/findings were fixed, introduced, or remain since a baseline
When a prior threat-model-* folder exists and the user wants a follow-up analysis

Single Analysis Mode:

Perform full threat model analysis of a repository or system
Generate threat model diagrams (DFD) from code
Perform STRIDE-A analysis on components and data flows
Validate security control implementations
Identify trust boundary violations and architectural risks
Write prioritized security findings with CVSS 4.0 / CWE / OWASP mappings

Comparing commits or reports:

To compare security posture between commits, use incremental mode with the older report as baseline

Files

ATTRIBUTION.mdAdded by AutoGineer869 B
LICENSELicence file added by AutoGineer1.0 KiB
SKILL.md5.7 KiB
references/analysis-principles.md28.9 KiB
references/diagram-conventions.md18.5 KiB
references/incremental-orchestrator.md33.5 KiB
references/orchestrator.md53.8 KiB
references/output-formats.md58.5 KiB
references/skeletons/skeleton-architecture.md6.1 KiB
references/skeletons/skeleton-assessment.md11.1 KiB
references/skeletons/skeleton-dfd.md3.3 KiB
references/skeletons/skeleton-findings.md7.7 KiB
references/skeletons/skeleton-incremental-html.md5.3 KiB
references/skeletons/skeleton-inventory.md5.3 KiB
references/skeletons/skeleton-stride-analysis.md6.2 KiB
references/skeletons/skeleton-summary-dfd.md2.8 KiB
references/skeletons/skeleton-threatmodel.md2.2 KiB
references/tmt-element-taxonomy.md8.5 KiB
references/verification-checklist.md69.9 KiB

LICENSE

MIT License

Copyright GitHub, Inc.

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.

Requirements and compatibility

Written for: GitHub Copilot

Works with: Claude Code, Claude apps, OpenAI Codex, GitHub Copilot, Cursor, Gemini CLI, Kiro, OpenCode, Goose, Amp, Roo Code, JetBrains Junie, Factory Droid, Devin (ex-Windsurf), Mistral Vibe, OpenHands, Letta

“Works with” means the tool reads the open Agent Skills format; a skill written for one tool may use features others lack.