npx skills add ...
npx skills add google/mantis --skill mantis-threat-model
Synthesizes trust boundaries, attack surfaces, and attacker profiles into a living threat model. Use as Stage B of the Knowledge Base generation process, reading architecture and entity definitions from the KB. Don't use for analyzing source code or extracting raw learnings from JSONL files.
npx skills add google/mantis --skill mantis-threat-model
Security Architect. Synthesizes trust boundaries, attack surfaces, and attacker
profiles into THREAT_MODEL.md based exclusively on the entities and
architecture defined in the Knowledge Base (KB).
/mantis-threat-model--state_root <dir>: parent of workspace/. If absent, use
./workspace/... relative to the current directory. Locates
.mantis_state.json, the KB, and the archive directory.--snapshot_id <id>: the SNAPSHOT_ID this pass is pinned to. Used ONLY as
the provenance value stamped into THREAT_MODEL.md (the KB_SNAPSHOT:
line). If absent, fall back to active_snapshot.snapshot_id from state; if
that is also absent or snapshot_pinned is false, the stamp is the literal
UNPINNED.--snapshot_root <dir>: accepted for interface uniformity but NOT used —
this stage never reads target source (Block A step 0, findings-only role).workspace/.mantis_state.json — pass_number (to archive per pass) and,
for provenance only, active_snapshot
({root, snapshot_id, snapshot_pinned}). Both optional; absent → degraded
(see Backward-compat).workspace/kb/architecture.md.workspace/kb/entities/*.md.workspace/kb/THREAT_MODEL.md from the previous pass, if
present — only its first KB_SNAPSHOT: line, for the freshness check in
step 0.workspace/kb/THREAT_MODEL.md (first line is a KB_SNAPSHOT: provenance
header).workspace/kb/THREAT_MODEL.md (if any) to
workspace/archive/kb/THREAT_MODEL_pass_${N}.md BEFORE overwriting.THREAT_MODEL.md (if any) to the pass archive, then
deterministically overwrites workspace/kb/THREAT_MODEL.md in-place.
Re-running a pass with an unchanged snapshot reproduces an equivalent model
plus a STALE banner (see step 0 and the final save step).Role for this stage (findings-only / KB-only). /mantis-threat-model NEVER
reads target source. Every input it uses — architecture.md, entities/*.md,
the prior THREAT_MODEL.md, and .mantis_state.json — is STATE-RELATIVE (read
under state_root/workspace, NEVER under CODE_ROOT). This stage therefore
takes Block A step 0's FINDINGS-ONLY path: SKIP Block A steps 2–6, but STILL
read active_snapshot from state for provenance, and NEVER stop merely because
a code root is unset or unpinned.
Maintain a high-level Threat Model that explicitly defines who the attackers are and where they can interact with the system, relying on the pre-processed entities in the KB.
Execute the threat modeling process as follows:
Resolve Snapshot Provenance, Freshness, and Archive the Prior Model:
a. Compute CUR (the snapshot this threat model is stamped against):
--snapshot_id was passed → CUR = that value.active_snapshot.snapshot_pinned is true → CUR =
active_snapshot.snapshot_id.CUR = the literal UNPINNED (degraded / today's behavior).b. Compute PREV_TM (what the last model was stamped against): read the
FIRST line matching ^KB_SNAPSHOT: in the existing
workspace/kb/THREAT_MODEL.md; its value (trimmed) is PREV_TM. If the file
is absent, has no such line, or the value is empty → PREV_TM = the empty
string "".
c. SYNC-DELTA DECISION (mechanical; exact string equality, no fuzzy compare):
CUR == "UNPINNED" → SYNC_OCCURRED = true (degraded: always re-derive).PREV_TM == "" → SYNC_OCCURRED = true (first run / legacy KB).PREV_TM != CUR → SYNC_OCCURRED = true (a sync or dirty edit
advanced the snapshot).PREV_TM == CUR) → SYNC_OCCURRED = false (snapshot unchanged since
the last model).d. Archive the prior model (per pass), so overwrite is non-destructive:
N: read "pass_number" from workspace/.mantis_state.json. If
missing or invalid, scan workspace/archive/ for folders matching
findings_pass_N or loopN_findings and set N = max_found + 1,
defaulting to 1 if no archives exist. (Same rule the architecture stage
uses.)workspace/kb/THREAT_MODEL.md exists: ensure workspace/archive/kb/
exists (mkdir -p workspace/archive/kb/) and COPY (do NOT move) the file
to workspace/archive/kb/THREAT_MODEL_pass_${N}.md. You will overwrite the
live file in step 3. If the file does not exist, skip the copy.state_root/workspace);
NEVER prefix CODE_ROOT.Carry CUR, SYNC_OCCURRED, and N forward into steps 1–3 and the final
save.
Read the Synthesized KB:
workspace/kb/architecture.md to understand the system's data flows
and high-level design.workspace/kb/entities/ to understand the individual
components and any historical constraints or vulnerability patterns mapped
to them by the /mantis-architecture stage.Analyze Trust Boundaries:
Synthesize the Threat Model:
workspace/kb/THREAT_MODEL.md (overwriting the old one).Include the following sections to ensure downstream planning agents have sufficient context:
System Overview Summary: A concise summary derived from
architecture.md.
Deployment Intent: State exactly one of Intent: PRODUCTION or
Intent: SAMPLE_OR_TEST_ONLY. This verdict has a large blast radius:
/mantis-critic marks EVERY finding SAMPLE_OR_TEST (dismissing the whole
pass) the instant it reads Intent: SAMPLE_OR_TEST_ONLY. So
SAMPLE_OR_TEST_ONLY is FAIL-CLOSED behind a mechanical checklist:
PRODUCTION-SIGNAL CHECKLIST — you may write Intent: SAMPLE_OR_TEST_ONLY
ONLY IF ALL five checks are TRUE. If ANY is FALSE, or the KB is silent on /
you are unsure about any one of them, you MUST write
Intent: PRODUCTION.
workspace/kb/entities/*.md is classified CRITICAL or
STANDARD availability (either implies an operated/production service).architecture.md names NO externally-reachable service, daemon, server,
API, or network endpoint, AND NO deployment/packaging descriptor
(systemd, Dockerfile/docker, kubernetes/k8s/helm, load balancer,
cloud/VPC/IaC, CI/CD publish or release).console_scripts/entry_points, a main()/service
binary, a published library or package manifest).test, tests,
example, examples, sample, samples, tutorial, demo, docs,
fixtures — and NONE lie under production source roots such as src,
lib, pkg, internal, cmd, app, server, or core.After a sync (SYNC_OCCURRED == true from step 0) you MUST re-run this
checklist from scratch against the CURRENT KB and MUST NOT inherit a prior
Intent: verdict — a sync can add production code to a tree that was
previously sample-only, which would otherwise silently dismiss every new
finding.
Trust Boundaries: Clear, rigorous definitions of where untrusted inputs
meet internal trusted states. Reference the specific entities (e.g.,
[Auth Module](entities/auth_module.md)).
Threat Actors & Vectors: Define the profiles of potential attackers (e.g., Unauthenticated Network Attacker, Malicious Local User) and the specific boundaries they can reach.
High-Risk Assets: The data, execution privileges, or availability targets an attacker wants to compromise. For availability targets, classify them into one of these Availability Tiers based on the KB:
CRITICAL: 24/7 immediate operational impact if disrupted.STANDARD: Important operations; short downtime is tolerable.LOW_CRITICALITY: Non-blocking utilities; disruption is a mild
annoyance.Stamp and save the model:
workspace/kb/THREAT_MODEL.md MUST be the provenance stamp
KB_SNAPSHOT: followed by CUR (from step 0) — e.g. KB_SNAPSHOT: <CUR>,
or KB_SNAPSHOT: UNPINNED in degraded mode. The next pass reads this back as
PREV_TM, and mantis-critic reads it as a KB freshness check.SYNC_OCCURRED == false (snapshot unchanged since the last model): you MAY
reuse the prior model's substance, but you MUST insert this STALE banner as
the line immediately AFTER the KB_SNAPSHOT: line:
> STALE: Threat model NOT re-evaluated this pass; carried unchanged from snapshot <CUR>.
If SYNC_OCCURRED == true: do NOT emit the STALE banner — you re-derived
every section fresh this pass, including the Deployment-Intent checklist.workspace/kb/THREAT_MODEL.md (STATE-RELATIVE; the prior
file was already copied to the pass archive in step 0d). Use your file-writing
tools; do not print the model to chat. When complete, notify the user.LOCATOR RESOLUTION (before reading ANY target code or artifact):
0. ROLE: If this skill NEVER reads target source (report, calibrate, reflect),
you are a FINDINGS-ONLY stage: skip steps 2-6; still read active_snapshot from
state for provenance/annotation; NEVER stop merely because a code root is unset.
1. Determine CODE_ROOT, in this priority order:
a. If --target_root is passed on THIS invocation, CODE_ROOT = --target_root.
It is AUTHORITATIVE and OVERRIDES SNAPSHOT_ROOT and the state fallback
(used when a caller hands you a prepared tree, e.g. a patched shadow).
b. Else if --snapshot_root (or SNAPSHOT_ROOT) is passed, use it.
c. Else read state_root/workspace/.mantis_state.json (state_root from
--state_root if passed, else ./workspace/... relative to the current dir)
-> active_snapshot.root / .snapshot_id / .snapshot_pinned.
d. Else (no arg AND no readable active_snapshot): CODE_ROOT = current directory,
treat snapshot_pinned = false (MODE-OFF). Do NOT stop.
2. SENTINEL CHECK (only if snapshot_pinned is true AND you did NOT take path 1a):
verify CODE_ROOT/.mantis_snapshot_id exists and equals SNAPSHOT_ID. If missing
or different -> STOP "snapshot sentinel mismatch". (A --target_root tree (1a) is
deliberately mutated and is sentinel-EXEMPT.)
3. PATH FIELDS:
- SNAPSHOT-RELATIVE (read under CODE_ROOT): code_paths entries; plan target_files
that are file paths. Strip ONLY a trailing ":<digits>". A code_paths entry
containing "://" is a URL/endpoint, NOT a file read. A code_paths entry that is
NOT of the form <existing-path>:<integer> is a non-source LOCATOR
(symbol/offset/endpoint): only check that the artifact/symbol exists; skip ALL
line-range and line-existence logic.
- STATE-RELATIVE (read/write under state_root/workspace, NEVER prefix CODE_ROOT):
kb_references, repro_file_path, reattack_file_path, helper scripts, report
files, and all state/findings JSON.
4. Never WRITE under CODE_ROOT when snapshot_pinned is true. Any command that
compiles, generates, or writes artifacts MUST run in a PRIVATE SHADOW copy
(mktemp -d from CODE_ROOT), never with cwd=CODE_ROOT. Read-only inspection may
cd into CODE_ROOT.
5. VCS-METADATA CARVE-OUT: history-log extraction and any VCS diff/blame command
run in the LIVE repository root (which still has .git/.hg/.repo), NOT CODE_ROOT
(the snapshot copy strips VCS metadata). Do NOT stop merely because CODE_ROOT
lacks .git/.hg/.repo.
6. Every shell command uses ABSOLUTE paths and sets its own working directory on
that call. Do NOT assume the working directory persists between calls.