Guardlink

[](https://www.npmjs.com/package/guardlink) [](https://github.com/Bugb-Technologies/guardlink/actions) [](LICENSE) [](https://nodejs.org) [](docs/SPEC.md)

Security annotations that live in your code. Your threat model updates when your code changes.

> This repository is secured by GuardLink. Run guardlink status . to see 272 annotations across 12 assets, 13 threats, and 10 controls — maintained by AI agents, validated in CI.

// @asset PaymentService (#payments) -- "Handles card transactions"
// @threat SQL_Injection (#sqli) [critical] cwe:CWE-89

// @mitigates #payments against #sqli using #prepared-stmts
app.post('/charge', async (req, res) => {
  const result = await db.query('SELECT * FROM cards WHERE id = $1', [req.body.id]);
});

// @exposes #payments to #idor [P1] cwe:CWE-639 -- "No ownership check"
app.get('/receipts/:id', async (req, res) => {
  const receipt = await db.query('SELECT * FROM receipts WHERE id = $1', [req.params.id]);
});

---

Install

npm install -g guardlink

Requires Node.js 18+.

Manual Installation

To install from source:

# 1. Build the project
npm run build

# 2. Link globally
npm link

To uninstall: npm unlink -g guardlink

Quick Start

# Initialize in your project (detects your AI agent automatically)
guardlink init

# Let AI annotate your project - Launch a coding agent to add annotations
guardlink annotate [prompt] [--mode inline|external]

# Let your AI coding agent annotate, or write annotations manually
# Then validate
guardlink validate .

# See your security posture
guardlink status .

Assets:        3    Mitigations:  4
Threats:       8    Exposures:    6  (3 unmitigated)
Controls:      5    Coverage:     62%

# Generate a full threat model report
guardlink report .

# Interactive HTML dashboard
guardlink dashboard .

# AI threat analysis (STRIDE, DREAD, PASTA, etc.)
guardlink threat-report stride --claude-code

# Interactive TUI with slash commands
guardlink

---

DEMO video

[](https://www.youtube.com/watch?v=a8wq7dAYtto)

---

Why GuardLink

Threat models rot. Teams do a session at the start of a project, someone creates a Confluence page, and it's stale by the next sprint. SAST scanners find 200 things with no context about what matters. Pen test reports sit in shared drives. The root cause is always the same: security knowledge lives outside the code.

GuardLink fixes this at three levels:

1. Annotations in code. Security decisions are structured comments next to the code they describe. When a developer writes a parameterized query, @mitigates #api against #sqli using #prepared-stmts lives right above it. When the code changes, the annotation is right there to update. The threat model is the code.

2. AI agents maintain it. GuardLink integrates with AI coding agents through MCP and behavioral directives. When your agent writes a route handler, it adds @exposes and @mitigates annotations automatically. The threat model maintains itself because the thing writing the code also writes the security context.

3. CI enforces it. guardlink validate fails on syntax errors. guardlink diff --fail-on-new blocks PRs that introduce unmitigated exposures. guardlink sarif exports to GitHub's Security tab. The threat model becomes a quality gate, not a checkbox.

Developer writes code
       ↓
AI agent adds security annotations
       ↓
CI validates on every PR
       ↓
Team reviews security posture in the diff
       ↓
Threat model is always current, always enforced

---

AI Agent Integration

GuardLink ships an MCP server and behavioral directives for AI coding agents. After guardlink init, your agent treats security annotations like type safety — adding them by default when writing security-relevant code.

guardlink init detects your agent and configures two things:

MCP server — tools to read the threat model, validate annotations, suggest annotations, and query threats by keyword. The agent can ask "what threats affect #api?" before writing code that touches the API.

Behavioral directive — a rule injected into your agent's instruction file (CLAUDE.md, .cursorrules, etc.) that says: when writing code that handles routes, auth, database access, file I/O, or external services, add GuardLink annotations.

Supported Agents

| Agent | Config File | MCP Support | |-------|------------|-------------| | Claude Code | CLAUDE.md + .mcp.json | ✅ Full | | Cursor | .cursorrules + .cursor/mcp.json | ✅ Full | | Windsurf | .windsurfrules + .windsurf/mcp.json | ✅ Full | | Cline | .clinerules + .cline/mcp.json | ✅ Full | | Codex | AGENTS.md | Directive only | | GitHub Copilot | .github/copilot-instructions.md | Directive only |

MCP Tools

| Tool | Description | |------|-------------| | guardlink_parse | Full threat model as JSON | | guardlink_validate | Check for errors and dangling references | | guardlink_status | Coverage summary | | guardlink_suggest | Suggest annotations for a code snippet | | guardlink_lookup | Query threats, controls, flows by keyword | | guardlink_threat_report | AI threat report (STRIDE, DREAD, etc.) | | guardlink_annotate | Build annotation prompt for the agent, with inline or .gal mode | | guardlink_report | Generate markdown report | | guardlink_dashboard | Generate HTML dashboard | | guardlink_sarif | Export SARIF 2.1.0 | | guardlink_diff | Compare threat model against a git ref | | guardlink_workspace_info | Workspace config, sibling repos, tag prefixes for cross-repo annotations |

Resources: guardlink://model, guardlink://definitions, guardlink://config

---

Commands

| Command | Description | |---------|-------------| | guardlink init [dir] | Initialize project with definitions, config, and agent integration | | guardlink annotate [prompt] [--mode inline\|external] | Launch a coding agent to add inline annotations or associated .gal files | | guardlink parse [dir] | Parse all annotations, output ThreatModel JSON | | guardlink status [dir] | Coverage summary: assets, threats, mitigations, exposures | | guardlink validate [dir] | Check for syntax errors, dangling refs, duplicate IDs | | guardlink validate --strict | Also fail on unmitigated exposures | | guardlink scan [dir] | Find unannotated security-relevant functions | | guardlink report [dir] | Markdown threat model with Mermaid architecture diagram | | guardlink dashboard [dir] | Interactive HTML threat model dashboard | | guardlink diff --from | Compare threat models between git refs | | guardlink diff --fail-on-new | Exit 1 if new unmitigated exposures found | | guardlink sarif [dir] | Export unmitigated exposures as SARIF 2.1.0 | | guardlink threat-report [fw] | AI threat report (stride/dread/pasta/attacker/rapid/general) | | guardlink threat-reports | List saved AI threat reports | | guardlink translate [prompt] | Generate CERT-X-GEN pentest templates from threat model findings | | guardlink ask | Ask a natural-language question about the threat model and codebase | | guardlink review [dir] | Interactive governance review — accept, remediate, or skip unmitigated exposures | | guardlink review --list | List reviewable exposures without prompting | | guardlink clear [dir] | Remove all annotations from source files (with --dry-run preview) | | guardlink sync [dir] | Sync agent instruction files with current threat model | | guardlink unannotated [dir] | List source files with no annotations | | guardlink link-project | Link repos into a shared workspace for cross-repo threat modeling | | guardlink link-project --add | Add a repo to an existing workspace | | guardlink link-project --remove | Remove a repo from a workspace | | guardlink merge | Merge per-repo report JSONs into a unified workspace dashboard | | guardlink report --format json | Generate report JSON with metadata (repo, workspace, commit SHA) | | guardlink config | Set AI provider and API key | | guardlink mcp | Start MCP server for AI agent integration |

---

Annotation Reference

GuardLink annotations can live in source comments in any language or in standalone .gal files. The parser supports //, #, --, /* */, """ """, and 25+ comment styles for inline annotations, plus raw GAL lines for externalized files.

> In standalone .gal files, drop the host-language comment prefix. // @exposes ... becomes @exposes .... Keep definitions in .guardlink/definitions.*; use .gal files for externalized relationship annotations. Use @source file: line: [symbol:] to point the following annotations at the real code location.

Definitions (shared, in .guardlink/definitions.js)

// @asset App.API (#api) -- "Express REST API serving mobile and web clients"
// @threat SQL_Injection (#sqli) [critical] cwe:CWE-89 -- "Unsanitized input reaches SQL query"
// @control Parameterized_Queries (#prepared-stmts) -- "All queries use bound parameters"

Relationships (in source files, next to the code)

# @mitigates #api against #sqli using #prepared-stmts -- "All queries parameterized"
# @exposes #api to #xss [P1] cwe:CWE-79 -- "User bio rendered without escaping"
# @accepts #info-disclosure on #api -- "Health endpoint is intentionally public"
# @transfers #sqli from #api to #database -- "DB handles untrusted input"

Externalized relationships (in .gal files)

@source file:src/auth/login.ts line:42 symbol:authenticate
@exposes #api to #xss [P1] cwe:CWE-79 -- "User bio rendered without escaping"
@audit #api -- "Review sanitization before release"
@comment -- "Same GAL syntax as inline comments, but without // or # prefixes"

Data Flow & Architecture

// @flow #api -> #database via "PostgreSQL wire protocol"
// @boundary #api  #cdn -- "TLS termination point"
// @handles pii on #api -- "Processes user email and address"
// @handles secrets on #auth -- "Manages JWT signing keys"

Operational

// @audit #api by "PenTest Corp" on 2025-03-15 -- "Annual penetration test"
// @validates #input-validation on #api using "Jest integration tests"
// @assumes #api -- "Rate limiting handled by API gateway"
// @owns #api by "backend-team"

All Annotation Types

| Verb | Purpose | Example | |------|---------|---------| | @asset | Define a component | @asset UserService (#users) | | @threat | Define a threat | @threat XSS (#xss) [high] cwe:CWE-79 | | @control | Define a security control | @control WAF (#waf) | | @mitigates | Control protects asset against threat | @mitigates #api against #sqli using #prepared-stmts | | @exposes | Asset vulnerable to threat | @exposes #api to #xss [P1] | | @confirmed | Threat verified exploitable (pentest/scan) | @confirmed #sqli on #api [critical] -- "Verified in pen test" | | @feature | Tag code with a product feature name | @feature "SSO Login" -- "Single sign-on authentication flow" | | @accepts | Risk acknowledged | @accepts #dos on #api -- "By design" | | @transfers | Risk moved between assets | @transfers #sqli from #api to #db | | @flow | Data flow between assets | @flow #api -> #db via "SQL" | | @boundary | Trust boundary | @boundary #api #external | | @handles | Data classification | @handles pii on #users | | @audit | Security audit record | @audit #api by "Firm" on 2025-01-01 | | @validates | Control verification | @validates #auth on #api using "tests" | | @assumes | Security assumption | @assumes #api -- "Behind VPN" | | @owns | Component ownership | @owns #api by "team-backend" | | @shield | AI exclusion zone | @shield #api requires #auth-check |

Severity: [critical]/[P0], [high]/[P1], [medium]/[P2], [low]/[P3]. External refs: cwe:CWE-89, capec:CAPEC-66, owasp:A03.

---

CI Integration

GitHub Actions

name: GuardLink
on: [pull_request]

jobs:
  guardlink:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
        with: { fetch-depth: 0 }

      - uses: actions/setup-node@v4
        with: { node-version: '20' }

      - run: npm install -g guardlink

      - name: Validate annotations
        run: guardlink validate .

      - name: Threat model diff
        run: guardlink diff --from origin/main --to HEAD

      - name: Export SARIF
        run: guardlink sarif . -o guardlink.sarif

      - uses: github/codeql-action/upload-sarif@v3
        with: { sarif_file: guardlink.sarif }

See [examples/github-action.yml](examples/github-action.yml) for a full example with PR comments and SARIF upload.

Multi-Repo CI

For workspace setups, GuardLink provides two additional workflow templates: a per-repo workflow that generates report JSON artifacts on every push, and a workspace merge workflow that runs weekly to combine all repos into a unified dashboard. See the [CI setup guide](examples/ci/README.md) for step-by-step instructions.

What CI Catches

• New route, no annotations: guardlink diff shows "+1 endpoint, 0 mitigations" — the team sees the gap.
• Agent annotated properly: diff shows "+1 asset, +2 mitigations, +1 exposure (IDOR)" — team reviews.
• Control removed: diff shows "-1 mitigation, +1 unmitigated exposure" — --fail-on-new blocks the PR.

SARIF

guardlink sarif exports unmitigated exposures and @confirmed findings as SARIF 2.1.0. Upload to GitHub Advanced Security: unmitigated @exposes appear as warnings or errors by severity; @confirmed exploitable findings appear as errors.

Pentest Integration

GuardLink bridges threat modeling and penetration testing in both directions.

From threat model to pentest templates — guardlink translate reads your @exposes annotations and generates CERT-X-GEN (CXG) pentest template stubs targeting the specific threats you've documented. Run it with any agent backend:

guardlink translate --claude-code
guardlink translate "focus on injection paths" --clipboard

From pentest results back to the threat model — Drop CXG scan result JSON files into .guardlink/pentest-findings/. GuardLink reads them automatically and:

• Injects findings as empirical evidence in guardlink threat-report and AI analyses
• Displays a Pentest Findings section in guardlink dashboard
• Teaches agents to cross-reference scan results against @exposes annotations

Marking verified findings — When a pentest or scan proves a threat is exploitable, add @confirmed to close the loop:

// @confirmed #sqli on App.API [critical] cwe:CWE-89 -- "CXG scan 2026-04: time-based blind SQLi on /login confirmed"

@confirmed is distinct from @exposes (hypothesis) — it means real, verified, not a false positive.

Handling evidence safely — Pentest finding JSON files in .guardlink/pentest-findings/ and generated templates in .guardlink/cxg-templates/ often contain live tokens, JWTs, credential payloads, and other replay-enabling material captured from successful exploits. Before running scans against any system you care about, add these directories to your repository's ignore file. GuardLink also supports opt-in surgical redaction (guardlink config set redact-evidence true) for enterprise users whose compliance posture requires no cleartext credentials at rest. See [docs/handling-evidence.md](docs/handling-evidence.md) for the full operational guide.

---

Multi-Repo Workspaces

In microservices architectures, a single repo only has part of the security picture. PaymentService is defined in repo-payments, exposed in repo-gateway, mitigated in repo-auth-lib. GuardLink workspaces link these repos so the threat model spans service boundaries.

# Link three repos into a workspace
guardlink link-project ./payment-svc ./auth-lib ./api-gateway \
  --workspace acme-platform

# E

…

## Source & license

This open-source MCP server is cataloged on AgentStack and links to its original source — we do not rehost the code.

- **Author:** [Bugb-Technologies](https://github.com/Bugb-Technologies)
- **Source:** [Bugb-Technologies/guardlink](https://github.com/Bugb-Technologies/guardlink)
- **License:** MIT
- **Homepage:** https://guardlink.bugb.io/

Install and usage instructions live in the source repository linked above.