Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx skills add vinnie357/claude-skills --skill anti-fabricationgit clone --depth 1 https://github.com/vinnie357/claude-skillsWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/vinnie357/claude-skills/anti-fabrication)<a href="https://agentmods.dev/skills/vinnie357/claude-skills/anti-fabrication"><img src="https://agentmods.dev/badge/skills/vinnie357/claude-skills/anti-fabrication/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/vinnie357/claude-skills/anti-fabrication"><img src="https://agentmods.dev/badge/skills/vinnie357/claude-skills/anti-fabrication.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector warn
SkillSpector: 3 findings, up to medium
These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →
- medium Excessive Agency · line 16 Skill enables autonomous high-impact decisions without human-in-the-loop verification. Critical operations (destructive commands, financial transactions, data deletion) should require explicit user confirmation.Fix: Add human-in-the-loop confirmation for destructive, irreversible, or high-impact operations. Never auto-execute commands that modify files, send data, or alter system state.
- medium Excessive Agency · line 69 Skill enables autonomous high-impact decisions without human-in-the-loop verification. Critical operations (destructive commands, financial transactions, data deletion) should require explicit user confirmation.Fix: Add human-in-the-loop confirmation for destructive, irreversible, or high-impact operations. Never auto-execute commands that modify files, send data, or alter system state.
- medium Excessive Agency · line 70 Skill enables autonomous high-impact decisions without human-in-the-loop verification. Critical operations (destructive commands, financial transactions, data deletion) should require explicit user confirmation.Fix: Add human-in-the-loop confirmation for destructive, irreversible, or high-impact operations. Never auto-execute commands that modify files, send data, or alter system state.
What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00044 | $0.02175 |
| Opus 5 | $0.00022 | $0.01087 |
| Sonnet 5 | $0.00009 | $0.00435 |
| Haiku 4.5 | $0.00004 | $0.00217 |
Grade A, and why
anti-fabrication scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 12d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
How it starts
The opening of the file, as written. The whole thing — 268 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Anti-Fabrication
Strict requirements for ensuring factual, measurable, and validated outputs in all work products including documentation, research, reports, and analysis.
Core Principles
Evidence-Based Outputs
- Base all outputs on actual analysis of real data using tool execution
- Execute Read, Glob, Bash, or other validation tools before making claims
- Never assume file existence, system capabilities, or feature presence without verification
- Validate integration recommendations through actual framework detection
Explicit Uncertainty
- Mark uncertain information as "requires analysis", "needs validation", or "requires investigation"
- State when information cannot be verified: "Unable to confirm without [specific check]"
- Acknowledge knowledge limitations rather than fabricating plausible-sounding content
Hedges vs directives
Hedge about the world. Never hedge about the instruction.
- A claim of fact with thin evidence carries a named marker:
unverified:, orrequires verification: <the check that would settle it>. - A directive carries no hedging verb. This covers an instruction, a procedure step, an acceptance criterion, a review finding, and an output contract.
- Write "Run
mise run cibefore pushing", never "you should probably runmise run ci". - The named-marker form replaces bare conditionals on claims too. "May", "likely", and "appears to" name no check, so they leave the reader nothing to act on.
Test a sentence by putting "You" in front of it. If it still reads as advice, it is a directive, so strip the hedge. If it answers "is this true?", keep the uncertainty and name the check.
Factual Language
- Use precise, factual language without superlatives or unsubstantiated performance claims
- Replace vague statements with specific, measurable observations
- Report what was actually observed, not what should theoretically be true
- Distinguish between verified facts and reasonable inferences
Prohibited Language and Claims
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 12d ago First seen · 268 lines · 44 tokens per session scan A 0cb369450ba6
anti-fabrication is a skill published in the GitHub repository vinnie357/claude-skills (25 stars, last pushed 2d ago), licensed MIT. It adds 44 tokens to every session and 2,175 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
Other skills, from other repositories
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Adversarial code review that assumes bugs exist and hunts for them. Use when asked to review code, find bugs, audit for correctness, stress-test a PR, or when someone says "tear this apart" or "what's wrong with this". Give no benefit of the doubt — every line is guilty until proven innocent.
gsd-ns-review
Route to the appropriate quality / review skill based on the user's intent. gsd-code-review-fix was absorbed by gsd-code-review --fix in #2790.
issue
Use when starting a chain from a GitHub issue — turning an issue URL or number into a triaged, planned, dispatched, and reviewed pull request. Classifies the thread (bug → root-cause discipline, feature → plan chain, question → drafted reply), synthesizes a spec from the issue's own acceptance criteria, then runs the…
gitnexus
A code-graph analysis add-on for examining an existing codebase, including symbols, call paths, execution flows, and effects across repositories. It can query GitNexus through its command-line or MCP interfaces.
cleanup-code-inspections
Reduce technical debt and improve code quality by systematically resolving static analysis warnings.
sonarqube-mcp
Provides SonarQube and SonarCloud integration patterns via the Model Context Protocol (MCP) server. Enables quality gate monitoring, issue discovery and triaging, pre-push code analysis, and rule education directly in the agent workflow. Use when the user wants to check quality gates, search for Sonar issues, analyze…