Trailmark Review Gate
Apply deterministic security gate rules to Trailmark structural diff evidence.
This skill does not replace line-level review. It produces a compact structural
packet reviewers can cite while they inspect the code.
When to Use
- Reviewing a branch, pull request, release diff, or fix commit
- Checking whether a change expands attack surface
- Looking for removed validation or authorization on reachable paths
- Comparing before/after taint, privilege-boundary, blast-radius, or
complexity signals
- Producing graph evidence for a differential review
When NOT to Use
- Single-snapshot analysis. Use
trailmark or trailmark-structural.
- Text-diff review only. Use
differential-review.
- Full vulnerability discovery. Use an audit or bug-finding workflow.
- One static finding. Use
trailmark-finding-triage.
- Tooling is unavailable and the user wants manual review only.
Rationalizations to Reject
| Rationalization |
Why It Is Wrong |
Required Action |
| "The line diff is small, so no graph gate is needed" |
Small changes can create new call paths |
Compare before/after graphs |
| "Graph gate passed, so the PR is secure" |
The gate only checks structural regressions |
Still perform line-level review |
| "Trailmark failed, so pass the gate" |
Tool failure is unknown risk, not success |
Emit UNKNOWN |
| "Tests pass, so removed validation is fine" |
Tests may miss affected entrypoint paths |
Review the removed path manually |
| "Only new code matters" |
Removed auth, validation, and callers can be higher risk than additions |
Review removals and path changes |
Workflow
Review Gate Progress:
- [ ] Step 1: Resolve before/after inputs
- [ ] Step 2: Build graph-evolution evidence
- [ ] Step 3: Normalize structural changes
- [ ] Step 4: Apply gate rules
- [ ] Step 5: Emit review packet and actions
Step 1: Resolve Inputs
Accept two refs, a branch name, a commit range, or before/after directories.
Do not check out branches unnecessarily. Prefer git diff, git show, and
git worktrees, following the graph-evolution snapshot workflow.
Step 2: Build Graph Evidence
Run graph-evolution or equivalent Trailmark before/after graph analysis.
Both snapshots must run engine.preanalysis() so taint, privilege-boundary,
blast-radius, complexity, and entrypoint signals are available.
Record Trailmark version and any feature probes. If graph construction fails,
emit UNKNOWN.
Step 3: Normalize Changes
Normalize evidence into:
- added, removed, and modified nodes
- added and removed edges
- entrypoint set changes
- taint membership changes
- privilege-boundary membership changes
- blast-radius changes
- complexity changes
- newly reachable sensitive sinks
- unresolved, proxy, or dynamic edge changes
Step 4: Apply Gate Rules
Apply the rules in references/gate-rules.md.
Gate verdicts are:
| Verdict |
Meaning |
FAIL |
A high-risk structural regression needs review before acceptance |
WARN |
A meaningful graph change needs reviewer attention |
PASS |
No configured structural gate fired |
UNKNOWN |
Trailmark failed or evidence is too incomplete |
Step 5: Emit Packet
Write the packet using
references/output-format.md, then hand it to
the branch reviewer. Use
references/review-integration.md when
combining this packet with differential-review or another PR review process.
Requirements
- Never mutate the user's working branch while comparing refs.
- Never report
PASS when Trailmark failed.
- Separate graph evidence from manual security judgment.
- Include exact changed nodes or paths for every
FAIL and WARN.
- Include limitations when parser, proxy, unresolved-call, or dynamic-dispatch
uncertainty affects the verdict.
1---2name: trailmark-review-gate3description: Runs a Trailmark structural review gate over a branch, pull request, fix commit, release diff, or git ref range to detect new entrypoints, new tainted paths, removed validation or authorization calls, privilege-boundary drift, blast-radius growth, complexity growth, and newly reachable sensitive sinks. Use when reviewing a PR, branch, remediation commit, or release diff where graph-level security regressions should be checked before merge.4---56# Trailmark Review Gate78Apply deterministic security gate rules to Trailmark structural diff evidence.9This skill does not replace line-level review. It produces a compact structural10packet reviewers can cite while they inspect the code.1112## When to Use1314- Reviewing a branch, pull request, release diff, or fix commit15- Checking whether a change expands attack surface16- Looking for removed validation or authorization on reachable paths17- Comparing before/after taint, privilege-boundary, blast-radius, or18 complexity signals19- Producing graph evidence for a differential review2021## When NOT to Use2223- Single-snapshot analysis. Use `trailmark` or `trailmark-structural`.24- Text-diff review only. Use `differential-review`.25- Full vulnerability discovery. Use an audit or bug-finding workflow.26- One static finding. Use `trailmark-finding-triage`.27- Tooling is unavailable and the user wants manual review only.2829## Rationalizations to Reject3031| Rationalization | Why It Is Wrong | Required Action |32|---|---|---|33| "The line diff is small, so no graph gate is needed" | Small changes can create new call paths | Compare before/after graphs |34| "Graph gate passed, so the PR is secure" | The gate only checks structural regressions | Still perform line-level review |35| "Trailmark failed, so pass the gate" | Tool failure is unknown risk, not success | Emit `UNKNOWN` |36| "Tests pass, so removed validation is fine" | Tests may miss affected entrypoint paths | Review the removed path manually |37| "Only new code matters" | Removed auth, validation, and callers can be higher risk than additions | Review removals and path changes |3839## Workflow4041```42Review Gate Progress:43- [ ] Step 1: Resolve before/after inputs44- [ ] Step 2: Build graph-evolution evidence45- [ ] Step 3: Normalize structural changes46- [ ] Step 4: Apply gate rules47- [ ] Step 5: Emit review packet and actions48```4950### Step 1: Resolve Inputs5152Accept two refs, a branch name, a commit range, or before/after directories.53Do not check out branches unnecessarily. Prefer `git diff`, `git show`, and54git worktrees, following the `graph-evolution` snapshot workflow.5556### Step 2: Build Graph Evidence5758Run `graph-evolution` or equivalent Trailmark before/after graph analysis.59Both snapshots must run `engine.preanalysis()` so taint, privilege-boundary,60blast-radius, complexity, and entrypoint signals are available.6162Record Trailmark version and any feature probes. If graph construction fails,63emit `UNKNOWN`.6465### Step 3: Normalize Changes6667Normalize evidence into:6869- added, removed, and modified nodes70- added and removed edges71- entrypoint set changes72- taint membership changes73- privilege-boundary membership changes74- blast-radius changes75- complexity changes76- newly reachable sensitive sinks77- unresolved, proxy, or dynamic edge changes7879### Step 4: Apply Gate Rules8081Apply the rules in [references/gate-rules.md](references/gate-rules.md).82Gate verdicts are:8384| Verdict | Meaning |85|---|---|86| `FAIL` | A high-risk structural regression needs review before acceptance |87| `WARN` | A meaningful graph change needs reviewer attention |88| `PASS` | No configured structural gate fired |89| `UNKNOWN` | Trailmark failed or evidence is too incomplete |9091### Step 5: Emit Packet9293Write the packet using94[references/output-format.md](references/output-format.md), then hand it to95the branch reviewer. Use96[references/review-integration.md](references/review-integration.md) when97combining this packet with `differential-review` or another PR review process.9899## Requirements100101- Never mutate the user's working branch while comparing refs.102- Never report `PASS` when Trailmark failed.103- Separate graph evidence from manual security judgment.104- Include exact changed nodes or paths for every `FAIL` and `WARN`.105- Include limitations when parser, proxy, unresolved-call, or dynamic-dispatch106 uncertainty affects the verdict.
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