Trading Card Analysis & eBay Listing Specialist

• Outcome: Review
• Latest audit: Sep 11, 2026 · 3:38 AM UTC
• Version: 2.0.5

Overview

This skill is mostly a coherent trading-card helper, but its required eBay listing template can insert unverified seller, shipping, and authenticity claims into marketplace copy.

Review and customize any generated eBay copy before publishing. Remove seller-status, feedback, shipping-speed, insurance, return-policy, and authenticity statements unless you can verify they are true for your account and the specific item. Optional eBay/PSA credentials are not required for basic use; only provide them through your host's normal secret-management path when you need live data.

A.I.G

Vulnerability Patterns

• Insecure Skill Coding Practices: Finds exploitable flaws such as hardcoded secrets or command injection
• Skill Instruction Hijacking: Alters the agent's session goals or safety constraints when the skill loads
• Agent Memory Poisoning: Writes attacker-controlled rules into memory that affect later sessions
• Remote Payload Retrieval and Execution: Fetches external code whose behavior can change after review
• Embedded Malicious Code: Ships malicious scripts inside the skill and executes them locally

Findings (1)

T09 · Insecure Skill Coding Practices

Warning

• Location: assets/ebay-listing-template.md:33

Finding

Unverified Seller, Fulfillment, and Authentication Claims in Listing Templates

Content

View full analysis

Vulnerability Details

File Location: assets/ebay-listing-template.md:33-43 and assets/ebay-listing-template.md:110-113; the template is mandated by SKILL.md:79-80
Vulnerability Type: Unverified fixed claims in generated marketplace content
Risk Level: Medium

Vulnerable Code

SKILL.md:79-80:

markdown

### eBay listing output
Use the bundled template in [assets/ebay-listing-template.md](assets/ebay-listing-template.md) when generating listing copy.

assets/ebay-listing-template.md:33-43:

markdown

## Shipping & Handling
🚚 **Same-Day Shipping** (orders by 2 PM EST)
📦 **Premium Packaging**: Team bags, toploaders, bubble mailers
🔒 **Insurance Included** on all orders $100+
📍 **Tracking Provided** for all shipments

## Seller Credentials
⭐ **99.8% Positive Feedback** ({FEEDBACK_COUNT}+ transactions)
🏆 **Top Rated Seller** with eBay Premium Service
🎯 **Card Specialist** - {YEARS_EXPERIENCE}+ years in the industry
🔍 **Authentication Guarantee** - 30-day return policy

assets/ebay-listing-template.md:110-113:

markdown

## Authenticity Guarantee
✅ Examined by vintage card specialist
✅ Period-appropriate printing and materials verified
✅ 30-day authenticity guarantee
✅ Detailed condition photos provided

Technical Analysis

The Skill explicitly directs the agent to use the bundled eBay template, but the template contains fixed assertions about same-day shipping, insurance, tracking, seller status, feedback percentage, professional expertise, return policies, and authentication. Most of these claims are not represented as optional placeholders and do not require verification from the user or a live marketplace integration.

An agent following the Skill can therefore reproduce these statements even when the seller never supplied or confirmed them. The issue conflicts with the factual-output requirements in SKILL.md:84-85 and SKILL.md:113, whic ...[truncated 1741 chars]

Remediation

View remediation

Remediation Suggestions

1. Replace every fixed seller or fulfillment assertion with an explicit placeholder, including:

   • {SHIPPING_CUTOFF}
   • {PACKAGING_METHOD}
   • {INSURANCE_POLICY}
   • {TRACKING_POLICY}
   • {FEEDBACK_PERCENTAGE}
   • {TOP_RATED_STATUS}
   • {SELLER_EXPERIENCE}
   • {RETURN_POLICY}
   • {AUTHENTICATION_BASIS}

2. Omit each field by default unless the user affirmatively supplies or verifies its value.

3. Add an instruction to SKILL.md requiring the agent to distinguish:

   • User-confirmed facts.
   • Facts verified through an approved live integration.
   • Unknown details that must be omitted or marked for verification.

4. Add a pre-output validation step that rejects unsupported claims concerning seller status, guarantees, authentication, fulfillment times, insurance, tracking, and return policies.

5. Replace categorical authentication language with neutral wording unless evidence is available. For example:

   markdown

   Authentication: {AUTHENTICATION_DETAILS_IF_VERIFIED}
   

6. Require the generated draft to include a verification checklist for any unresolved marketplace-policy or seller-specific fields.

7. Add template-level comments making clear that placeholders must never be populated with invented defaults.

SkillSpector

Vulnerability Patterns

• Excessive Agency: Unrestricted Tool Access, Autonomous Decision Making, Scope Creep
• System Prompt Leakage: Direct Leakage, Indirect Extraction, Tool-Based Exfiltration
• MCP Tool Poisoning: Hidden Instructions, Unicode Deception, Parameter Description Injection
• Prompt Injection: Instruction Override, Hidden Instructions, Exfiltration Commands
• Data Exfiltration: External Transmission, Env Variable Harvesting, File System Enumeration

Findings (5)

Direct Prompt Extraction

High

• Category: System Prompt Leakage
• Confidence: 85% confidence

Finding

Skill contains instructions that could directly expose system prompts, internal rules, or hidden instructions to users or external parties.

Content

Scanner excerpt · SKILL.md (reported line 69)May include surrounding context.

md

Read [CREDENTIALS.md](CREDENTIALS.md) only when the user needs integration setup. This package does not include bundled live eBay or PSA client implementations.

## Output guidelines

### Card analysis
Return:

Autonomous Decision Making

Medium

• Category: Excessive Agency
• Confidence: 80% confidence

Finding

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.

Content

Scanner excerpt · SKILL.md (reported line 65)May include surrounding context.

md

- `EBAY_USER_TOKEN`
- `PSA_API_KEY`

Do not ask users to create home-directory credential files. Prefer runtime environment variables or the host's secret management.

Read [CREDENTIALS.md](CREDENTIALS.md) only when the user needs integration setup. This package does not include bundled live eBay or PSA client implementations.

Intent-Code Divergence

Medium

• Category: Not specified by scanner
• Confidence: 93% confidence

Finding

The template includes hardcoded seller credential and service claims like '99.8% Positive Feedback,' 'Top Rated Seller,' years of experience, and an 'Authentication Guarantee' while presenting them as reusable listing text. If users copy this without customizing to truthful seller-specific facts, it can produce deceptive listings, platform policy violations, and consumer fraud exposure. In this skill context, the risk is elevated because the file is explicitly designed to generate marketplace listings that may be published verbatim.

Content

No source excerpt is available for this finding.

Context-Inappropriate Capability

Medium

• Category: Not specified by scanner
• Confidence: 88% confidence

Finding

The manifest focuses on evaluating individual cards, estimating value, grading decisions, comps, and optimizing eBay listings. The weekly portfolio review, profit-taking, stop-loss evaluation, and concentration-risk triggers describe ongoing investment portfolio management, which is a distinct capability not disclosed in the manifest.

Content

No source excerpt is available for this finding.

Context-Inappropriate Capability

Medium

• Category: Not specified by scanner
• Confidence: 83% confidence

Finding

The manifest describes card evaluation, grading guidance, market comps, and eBay listing optimization, with optional enrichment from eBay and PSA data. This document adds capabilities for tracking social media influencer sentiment and economic market indicators, which are not clearly justified as necessary for the stated skill scope and materially broaden it into general market surveillance.

Content

No source excerpt is available for this finding.