threat-model

> Codex skill: MCP threat-model artifact for PR / compliance review > (iter 112 → iter 114). User-labelled "enterprise gold."

What it does

Renders the existing mcp-scan findings as a clean threat-model artifact in the shape a security / compliance reviewer wants to see attached to a PR:

MCP Threat Model

  Allowed tools:         3
  Denied tools:          14
  Dangerous permissions: 0
  Secrets reachable:     no
  Network access:        no
  Shell access:          no
  File write:            no
  Default-deny policy:   yes
  Audit log:             yes

Verdict: clean (exit 0)

Same underlying scan as mcp-scan, presented as a single-screen artifact.

| Verdict | Exit | Triggers | |---|---|---| | clean | 0 | no dangerous perms, no secret exposure | | medium | 1 | network OR file-write granted, OR no audit log | | high | 2 | shell granted OR default-deny OFF OR secrets reachable |

The "secrets reachable" heuristic is conservative: true when MCP is in use AND deny rules don't guard .env* AND allow rules include any Read(...) grant.

Usage from Codex

/threat-model path=./my-harness
/threat-model path=./my-harness bundle=true

Equivalent CLI

bash
harness threat-model ./my-harness                # text artifact
harness threat-model ./my-harness --json         # full envelope
harness threat-model ./my-harness --bundle       # ADR-031 schema-1
harness threat-model ./my-harness --out tm.json  # write to file

When to attach this to a PR

• Adding a new MCP server / tool
• Loosening a permission allow rule
• Pulling in a new dependency that exposes shell/network capabilities
• Any change to .harness/mcp-policy.json or .claude/settings.json

permissions

The artifact is small enough to paste verbatim into the PR description.

Related skills

• validate-harness (iter 22) — release-readiness umbrella (includes

mcp-scan)

• score-harness (iter 114) — broader 0-100 scorecard; MCP safety is

one of its 5 dimensions

• repo-genome (iter 114) — pre-scaffold readiness; MCP risk is one of

its 7 sections

See also

• ADR-022 — MCP primitive · ADR-030 — Discovery Loop · ADR-031 — Bundle Pattern