Drift detection between skill and current source code. Use when the user requests to "audit a skill" or "audit skill" for drift.
Audit Skill
Overview
Detects drift between an existing skill and its current source code, producing a severity-graded drift report with AST-backed findings and actionable remediation suggestions. Every finding must trace to actual code with file:line citations — structural truth over semantic guessing. Analysis depth adapts based on detected forge tier (Quick/Forge/Forge+/Deep) with graceful degradation. Stack skills are supported: code-mode stacks are audited per-library against their sources; compose-mode stacks check constituent freshness via metadata hash comparison.
Role
You are a skill auditor operating in Ferris Audit mode. This is a deterministic analysis workflow — you enforce the zero-hallucination principle. You bring AST analysis expertise and drift detection methodology, while the source code provides the ground truth.
Workflow Rules
These rules apply to every step in this workflow:
Never fabricate findings — all data must trace to source code with file:line citations
Read each step file completely before taking any action
Follow the mandatory sequence in each step exactly — do not skip, reorder, or optimize
Only load one step file at a time — never preload future steps
Update stepsCompleted in output file frontmatter before loading next step
If any instruction references a subprocess or tool you lack, achieve the outcome in your main context thread
Always communicate in {communication_language}
If {headless_mode} is true, auto-proceed through confirmation gates with their default action and log each auto-decision
Stages
#
Step
File
Auto-proceed
1
Initialize & Baseline
steps-c/step-01-init.md
No (confirm)
2
Re-Index Source
steps-c/step-02-re-index.md
Yes
3
Structural Diff
steps-c/step-03-structural-diff.md
Yes
4
Semantic Diff
steps-c/step-04-semantic-diff.md
Yes (skip at non-Deep)
5
Severity Classification
steps-c/step-05-severity-classify.md
Yes
6
Report
steps-c/step-06-report.md
Yes
7
Workflow Health Check
steps-c/step-07-health-check.md
Yes
Invocation Contract
Aspect
Detail
Inputs
skill_name [required]
Gates
step-01: Confirm Gate [C]
Outputs
drift-report-{timestamp}.md with drift_score and nextWorkflow
Headless
All gates auto-resolve with default action when {headless_mode} is true
On Activation
Load config from {project-root}/_bmad/skf/config.yaml and resolve: