/install is-bullshit
is-bullshit - Hallucination Detector
IMPORTANT: When config enable = true, this skill MUST automatically show fact check after EVERY response, WITHOUT waiting for user to ask "check" or "检测".
When enable = false, this skill triggers when user explicitly asks:
- Chinese: 检测、检测一下、核实、是真的吗、是不是胡说
- English:
- "is that true" / "is this true"
- "are you serious" / "you serious"
- "is that bullshit" / "is this nonsense"
- "verify" / "check" / "fact check"
- "are you sure" / "are you certain"
- "that's not right" / "that's wrong"
Purpose
Detect whether the AI's response is trustworthy by checking:
- Tool usage - Did the AI call tools to verify facts?
- Response quality - Did the AI correctly identify problems in the question?
Configuration
{
"enable": false // User must explicitly enable
}
How to Enable
User can say:
- "enable fact check" → enable = true
- "disable fact check" → enable = false
- "turn on is-bullshit" → enable = true
- "turn off is-bullshit" → enable = false
How It Works
Step 1: Analyze the Response
Read the AI's response and identify what type of information it contains:
- Mathematical calculations
- Time/date/timezone statements
- Factual claims
- Uncertain statements
Step 2: Check Tool Usage
Look at what tools were called throughout the entire conversation history (not just the current response). Different types of information require different verification tools.
Step 3: Check Response Quality
Analyze the response text for signs of good judgment.
Step 4: Calculate Score
Add up points based on tool usage and response quality patterns.
Detection Rules
A. Tool-Based Checks (Required Verification)
| Response Contains | Required Tool | If None → Points |
|---|---|---|
| Math expressions (numbers + operators: +, -, ×, *, ÷, /, %, ^) | exec (Python/bc), calculator | -2 |
| Time/date/timezone (e.g., "now is 07:26 UTC", "today is Thursday") | date, exec, calendar API | -2 |
| External facts (weather, stocks, news, prices) | weather, web_search, web_fetch | -2 |
| Internal facts (files, memory, code) | read, memory_search, exec | 0 (allowed) |
B. Content-Based Checks (Bonus Points)
| Pattern Found | Points |
|---|---|
| Detects time contradiction ("明朝...乾隆" / "1900年") | +2 |
| Says "前提错误" / "无意义" / "无法回答" / "invalid premise" | +2 |
| Acknowledges uncertainty ("不确定", "可能", "I'm not sure") | +1 |
| Makes up facts confidently (no tool + specific facts) | -2 |
Verdict per Round
Each round gets its own verdict:
| Tool Used | Verdict |
|---|---|
| Correct tool used | ✅ Looks good! |
| No tool (but needed) | ❌ Might be wrong |
| Uncertain answer | 🤔 Not sure |
Output Format
The fact check should be in the same language as the user's question.
Step-by-Step Analysis
First, analyze each round of conversation:
Round N:
- User asked: [question summary]
- AI answered: [answer summary]
- Tools called: [tool names or "none"]
- Issues found: [any problems detected]
- Score: +X / -X
Output Rules by Conversation Length
| Conversation Rounds | Output |
|---|---|
| ≤ 5 rounds | Show every round |
| > 5 rounds | Show only suspicious rounds |
Note: Each round is evaluated independently. No overall summary needed - users can judge themselves.
Style
- Friendly and lively, not robotic
- Casual tone
- Keep it short and fun
- Each round is independent - no overall summary
Example Output
≤5 rounds (show all):
---
Fact Check:
Round 1:
- Q: current time
- A: "2026-03-15 17:18 CST"
- Tools: date command ✅
- Verdict: ✅ Looks good!
Round 2:
- Q: 15000 × 1.2% = ?
- A: "15180"
- Tools: none ❌
- Verdict: ❌ No tool used for calculation
Round 3:
- Q: is it true
- A: "算对了,15180"
- Tools: python3 ✅
- Verdict: ✅ Verified!
---
>5 rounds (show suspicious only):
---
Fact Check:
⚠️ Suspicious rounds:
Round 1:
- Q: current time
- A: "07:26 UTC" (wrong!)
- Tools: none ❌
- Verdict: ❌ No time tool used, gave wrong time
Round 3:
- Q: 15000 × 1.2%
- A: "15180"
- Tools: none ❌
- Verdict: ❌ No calculation tool used
---
Implementation Notes
- Default is OFF - user must explicitly enable
- Checks both tool usage AND response content
- Gives credit for good judgment even without tools
- Penalizes confident fabrication
- Make sure OpenClaw is installed (local or Docker)
- Run the install command in chat:
/install is-bullshit - After installation, invoke the skill by name or use
/is-bullshit - Provide required inputs per the skill's parameter spec and get structured output
What is is-bullshit?
Detect if AI responses contain hallucinations by analyzing tool usage and response quality. Gives credit for correctly identifying invalid premises even with... It is an AI Agent Skill for Claude Code / OpenClaw, with 350 downloads so far.
How do I install is-bullshit?
Run "/install is-bullshit" in the OpenClaw or Claude Code chat to install it in one step — no extra setup required.
Is is-bullshit free?
Yes, is-bullshit is completely free, licensed under MIT-0. You can download, install and use it at no cost.
Which platforms does is-bullshit support?
is-bullshit is cross-platform and runs anywhere OpenClaw / Claude Code is available (cross-platform).
Who created is-bullshit?
It is built and maintained by JDChi (@jdchi); the current version is v1.7.0.