---

name: epistemic-checkpoint description: | Force verification before answering questions involving versions, dates, status, or "current" state. Prevents hallucinations at the REASONING level by checking assertions.yaml and WebSearch before forming beliefs. Triggers on software versions, release status, dates, and package versions.

Epistemic Checkpoint

Force verification before answering questions involving versions, dates, status, or "current" state.

Purpose

Prevents the ROOT CAUSE of hallucinations - not just blocking wrong output, but preventing wrong REASONING. Claude's training data is stale; this skill forces verification before forming beliefs.

Triggers

Activate this skill when the question involves ANY of:

• Software versions (.NET, Node, React, Python, etc.)
• Release status (preview, LTS, GA, RC, deprecated)
• "Current" or "latest" anything
• Dates that might be after training cutoff
• Package versions
• API deprecations

MANDATORY Protocol

Step 1: Recognize Uncertainty

Say to yourself: "My training data may be stale for: [topic]"

Step 2: Check Local Ground Truth

CopyRead ${CLAUDE_PLUGIN_ROOT}/blackboard/assertions.yaml
Search for relevant entries

If found - use that value with high confidence.

Step 3: If Not in Assertions - WebSearch

CopyWebSearch("[software] [version] release date site:official-docs")
WebSearch("[software] LTS release 2025")

Prefer official sources:

• microsoft.com/dotnet for .NET
• nodejs.org for Node
• python.org for Python

Step 4: State Verified Facts

Say: "Based on [source], [software] [version] is [status] as of [date]."

Step 5: THEN Proceed

Only now answer the actual question with the verified baseline.

Red Flag Thoughts (REJECT THESE)

Anti-Pattern Examples

WRONG:

Copy"If targeting .NET 10 preview, use C# 14 extension types..."

CORRECT:

Copy"Let me verify .NET 10 status... [WebSearch] ...
.NET 10 is LTS (released November 2025), not preview.
Standard extension methods work fine."

WRONG:

Copy"React 19 is still in beta, so..."

CORRECT:

Copy"Checking React 19 status... [WebSearch] ...
React 19 was released December 2024 as stable.
Proceeding with React 19 stable patterns."

Common Danger Patterns

Output Format

When this skill activates, structure your verification as:

CopyEpistemic Checkpoint

Claim to verify: [what you were about to assume]
Source checked: [assertions.yaml / WebSearch / official docs]
Verified fact: [the actual truth]
Confidence: [high/medium/low]

Proceeding with verified baseline...