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.
This skill inherits all available tools. When active, it can use any tool Claude has access to.
Force verification before answering questions involving versions, dates, status, or "current" state.
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.
Activate this skill when the question involves ANY of:
Say to yourself: "My training data may be stale for: [topic]"
Read ${CLAUDE_PLUGIN_ROOT}/blackboard/assertions.yaml
Search for relevant entries
If found - use that value with high confidence.
WebSearch("[software] [version] release date site:official-docs")
WebSearch("[software] LTS release 2025")
Prefer official sources:
Say: "Based on [source], [software] [version] is [status] as of [date]."
Only now answer the actual question with the verified baseline.
| If you think... | Actually do... |
|---|---|
| "I'm pretty sure .NET 10 is..." | WebSearch to verify |
| "This is probably still preview" | Check assertions.yaml |
| "I remember this from training" | Training is stale, verify |
| "This is a simple factual question" | Simple facts are often WRONG |
| "The user said it's preview" | User might be wrong too, verify |
WRONG:
"If targeting .NET 10 preview, use C# 14 extension types..."
CORRECT:
"Let me verify .NET 10 status... [WebSearch] ...
.NET 10 is LTS (released November 2025), not preview.
Standard extension methods work fine."
WRONG:
"React 19 is still in beta, so..."
CORRECT:
"Checking React 19 status... [WebSearch] ...
React 19 was released December 2024 as stable.
Proceeding with React 19 stable patterns."
| Topic | Danger Pattern | Likely Truth |
|---|---|---|
| .NET | "preview", "not released" | .NET 10 LTS since Nov 2025 |
| React | "beta", "experimental" | React 19 stable since Dec 2024 |
| Node | "current" without version | Always specify exact version |
| Python | "3.x is latest" | Verify - 3.13+ exists |
When this skill activates, structure your verification as:
Epistemic 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...