Manage evidence freshness by identifying stale decisions and providing governance actions

Evidence Freshness Management Manages evidence freshness by identifying stale decisions and providing governance actions. Implements FPF B.3.4 (Evidence Decay). Key principle: Evidence is perishable. Decisions built on expired evidence carry hidden risk. Quick Concepts What is "stale" evidence? Every piece of evidence has a valid until date. A benchmark from 6 months ago may no longer reflect current system performance. A security audit from before a major dependency update doesn't account for new vulnerabilities. When evidence expires, the decision it supports becomes questionable not necessarily wrong, just unverified. What is "waiving"? Waiving = "I know this evidence is stale, I accept the risk temporarily." Use it when: You're about to launch and don't have time to re run all tests The evidence is only slightly expired and probably still valid You have a scheduled date to refresh it properly A waiver is NOT ignoring the problem it's explicitly documenting that you know about the risk and accept it until a specific date. The Three Actions Situation Action What it does Evidence is old but decision is still good Refresh Re run the test, get fresh evidence Decision is obsolete, needs rethinking Deprecate Downgrade hypothesis, restart evaluation Accept risk temporarily Waive Record the risk acceptance with deadline Action (Run Time) Step 1: Generate Freshness Report 1. List all evidence files in .fpf/evidence/ 2. For each evidence file: Read valid until from frontmatter Compare with current date Classify as FRESH, STALE, or EXPIRED Step 2: Present Report Step 3: Handle User Actions Based on user response, perform one of: Refresh User: "Refresh the redis caching evidence" 1. Navigate to the hypothesis in .fpf/knowledge/L2/ 2. Re run validation to create fresh evidence Deprecate User: "Deprecate the auth module decision" 1. Move hypothesis from L2 to L1 (or L1 to L0) 2. Create deprecation record: 3. Move the hypothesis file: Waive User: "Waive the benchmark until February" 1. Create waiver record: Natural Language Usage You don't need to memorize evidence IDs. Just describe what you want. Example Workflow WLNK Principle A hypothesis is STALE if any of its evidence is expired (and not waived). This is the Weakest Link (WLNK) principle: reliability = min(all evidence). One stale piece makes the whole decision questionable. Audit Trail All actions are logged: Action What's Recorded Deprecate from layer, to layer, reason, date Waive evidence id, until date, rationale, date Files created in .fpf/evidence/ : deprecate {hypothesis} {date}.md waiver {evidence} {date}.md Common Workflows Weekly Maintenance Pre Release After Major Change

decay