jp-invoice-number-check

• Outcome: Pass
• Latest audit: Nov 10, 2026 · 4:57 AM UTC
• Version: 1.3.0

Overview

The scanners rated this skill benign because its reported external API calls appear aligned with invoice-number checks, though the scan was partial and confidence is medium.

Before installing, consider whether you want invoice-related information sent to the external JPVerify service and whether you are comfortable setting up an API key or using a paid wallet option. The benign verdict is not a guarantee of zero risk, and some reference checks were incomplete.

A.I.G

Vulnerability Patterns

• 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
• Unauthorized Access and Privilege Escalation: Obtains permissions beyond the task's legitimate needs

SkillSpector

Vulnerability Patterns

• Data Exfiltration: External Transmission, Env Variable Harvesting, File System Enumeration
• Prompt Injection: Instruction Override, Hidden Instructions, Exfiltration Commands
• Privilege Escalation: Excessive Permissions, Sudo/Root Execution, Credential Access
• Supply Chain: Unpinned Dependencies, External Script Fetching, Obfuscated Code
• Excessive Agency: Unrestricted Tool Access, Autonomous Decision Making, Scope Creep

Findings (32)

External Transmission

Medium

• Category: Data Exfiltration
• Confidence: 50% confidence

Finding

Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.

Content

Scanner excerpt · SKILL.md (reported line 34)May include surrounding context.

md

1. **API key (recommended).** If the environment has `JPVERIFY_API_KEY` (a `jpv_live_…` key the user created), send it on every call:
   - HTTP: header `Authorization: Bearer $JPVERIFY_API_KEY` (or `X-API-Key`).
   - MCP: if the JPVerify Claude Code plugin is installed, the `jpverify` MCP server is already configured and uses the key saved in the plugin's settings (`/plugin` → JPVerify → Configure), not `JPVERIFY_API_KEY`. Otherwise: `claude mcp add --transport http jpverify https://api.jpverify.com/mcp --header "Authorization: Bearer $JPVERIFY_API_KEY" --header "X-JPVerify-Client: jp-invoice-number-check/1.3.0"`
   Each successful call is deducted from the user's prepaid USD credits; failed or invalid calls are refunded automatically. Before a large batch, check the balance for free: `GET https://api.jpverify.com/v1/account/balance` with the same header, or the MCP tool `jpverify_balance`.
2. **x402 wallet.** If you have an x402 client with USDC on Base (`eip155:8453`) and the user a

External Transmission

Medium

• Category: Data Exfiltration
• Confidence: 50% confidence

Finding

Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.

Content

Scanner excerpt · SKILL.md (reported line 35)May include surrounding context.

md

lready configured and uses the key saved in the plugin's settings (`/plugin` → JPVerify → Configure), not `JPVERIFY_API_KEY`. Otherwise: `claude mcp add --transport http jpverify https://api.jpverify.com/mcp --header "Authorization: Bearer $JPVERIFY_API_KEY" --header "X-JPVerify-Client: jp-invoice-number-check/1.3.0"`
   Each successful call is deducted from the user's prepaid USD credits; failed or invalid calls are refunded automatically. Before a large batch, check the balance for free: `GET https://api.jpverify.com/v1/account/balance` with the same header, or the MCP tool `jpverify_balance`.
2. **x402 wallet.** If you have an x402 client with USDC on Base (`eip155:8453`) and the user approved a budget, call without a key: the API answers HTTP 402 with the exact price; sign and retry with `PAYMENT-SIGNATURE`. Pay only within the approved budget.
3. **Neither.** Do not pay and do not invent a key. The MCP server also works without a key for the free tool `jpverify_guide` (`claude mcp

External Transmission

Medium

• Category: Data Exfiltration
• Confidence: 50% confidence

Finding

Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.

Content

Scanner excerpt · SKILL.md (reported line 101)May include surrounding context.

API key:

bash

curl -X POST https://api.jpverify.com/v1/jp/invoice-registrations/verify \
  -H "Authorization: Bearer $JPVERIFY_API_KEY" \
  -H "X-JPVerify-Client: jp-invoice-number-check/1.3.0" \
  -H "Content-Type: application/json" \

External Transmission

Medium

• Category: Data Exfiltration
• Confidence: 50% confidence

Finding

Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.

Content

Scanner excerpt · SKILL.md (reported line 112)May include surrounding context.

md

import os, requests

response = requests.post(
    "https://api.jpverify.com/v1/jp/invoice-registrations/verify",
    headers={"Authorization": f"Bearer {os.environ['JPVERIFY_API_KEY']}",
             "X-JPVerify-Client": "jp-invoice-number-check/1.3.0"},
    json={"registration_number": "T1013301046627", "response_language": "both"},

External Transmission

Medium

• Category: Data Exfiltration
• Confidence: 50% confidence

Finding

Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.

Content

Scanner excerpt · references/examples.md (reported line 31)May include surrounding context.

POST /v1/jp/invoices/check-issuer — $0.05

bash

curl -X POST https://api.jpverify.com/v1/jp/invoices/check-issuer \
  -H "Authorization: Bearer $JPVERIFY_API_KEY" \
  -H "X-JPVerify-Client: jp-invoice-number-check/1.3.0" \
  -H "Content-Type: application/json" \

External Transmission

Medium

• Category: Data Exfiltration
• Confidence: 50% confidence

Finding

Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.

Content

Scanner excerpt · references/examples.md (reported line 42)May include surrounding context.

md

import os, requests

response = requests.post(
    "https://api.jpverify.com/v1/jp/invoices/check-issuer",
    headers={"Authorization": f"Bearer {os.environ['JPVERIFY_API_KEY']}",
             "X-JPVerify-Client": "jp-invoice-number-check/1.3.0"},
    json={"registration_number": "T1013301046627", "supplier_name": "株式会社ABC", "address": "東京都千代田区千代田1-1", "invoice_date": "2026-11-01", "response_language": "both"},

External Transmission

Medium

• Category: Data Exfiltration
• Confidence: 50% confidence

Finding

Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.

Content

Scanner excerpt · references/examples.md (reported line 77)May include surrounding context.

POST /v1/jp/invoices/check-issuer-batch — $0.04 per item

bash

curl -X POST https://api.jpverify.com/v1/jp/invoices/check-issuer-batch \
  -H "Authorization: Bearer $JPVERIFY_API_KEY" \
  -H "X-JPVerify-Client: jp-invoice-number-check/1.3.0" \
  -H "Content-Type: application/json" \

External Transmission

Medium

• Category: Data Exfiltration
• Confidence: 50% confidence

Finding

Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.

Content

Scanner excerpt · references/examples.md (reported line 88)May include surrounding context.

md

import os, requests

response = requests.post(
    "https://api.jpverify.com/v1/jp/invoices/check-issuer-batch",
    headers={"Authorization": f"Bearer {os.environ['JPVERIFY_API_KEY']}",
             "X-JPVerify-Client": "jp-invoice-number-check/1.3.0"},
    json={"items": [{"registration_number": "T1013301046627", "supplier_name": "宏達株式会社", "invoice_date": "2026-10-31"}], "response_language": "both"},

External Transmission

Medium

• Category: Data Exfiltration
• Confidence: 50% confidence

Finding

Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.

Content

Scanner excerpt · SKILL.md (reported line 37)May include surrounding context.

md

id USD credits; failed or invalid calls are refunded automatically. Before a large batch, check the balance for free: `GET https://api.jpverify.com/v1/account/balance` with the same header, or the MCP tool `jpverify_balance`.
2. **x402 wallet.** If you have an x402 client with USDC on Base (`eip155:8453`) and the user approved a budget, call without a key: the API answers HTTP 402 with the exact price; sign and retry with `PAYMENT-SIGNATURE`. Pay only within the approved budget.
3. **Neither.** Do not pay and do not invent a key. The MCP server also works without a key for the free tool `jpverify_guide` (`claude mcp add --transport http jpverify https://api.jpverify.com/mcp`); use it to confirm which call fits, then tell the user they can create a free account with starter credit at https://www.jpverify.com/signup?ref=jp-invoice-number-check and set `JPVERIFY_API_KEY`.

Always send `X-JPVerify-Client: jp-invoice-number-check/1.3.0` on HTTP calls. Never print, log or share the API key.

External Transmission

Medium

• Category: Data Exfiltration
• Confidence: 50% confidence

Finding

Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.

Content

Scanner excerpt · SKILL.md (reported line 125)May include surrounding context.

bash

# No key: shows the HTTP 402 x402 price; pay with an x402 client and retry with PAYMENT-SIGNATURE.
curl -i -X POST https://api.jpverify.com/v1/jp/invoice-registrations/verify \
  -H "X-JPVerify-Client: jp-invoice-number-check/1.3.0" \
  -H "Content-Type: application/json" \
  -d '{"registration_number": "T1013301046627", "response_language": "both"}'

External Transmission

Medium

• Category: Data Exfiltration
• Confidence: 60% confidence

Finding

Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.

Content

Scanner excerpt · SKILL.md (reported line 101)May include surrounding context.

API key:

bash

curl -X POST https://api.jpverify.com/v1/jp/invoice-registrations/verify \
  -H "Authorization: Bearer $JPVERIFY_API_KEY" \
  -H "X-JPVerify-Client: jp-invoice-number-check/1.3.0" \
  -H "Content-Type: application/json" \

External Transmission

Medium

• Category: Data Exfiltration
• Confidence: 70% confidence

Finding

Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.

Content

Scanner excerpt · SKILL.md (reported line 111)May include surrounding context.

python

import os, requests

response = requests.post(
    "https://api.jpverify.com/v1/jp/invoice-registrations/verify",
    headers={"Authorization": f"Bearer {os.environ['JPVERIFY_API_KEY']}",
             "X-JPVerify-Client": "jp-invoice-number-check/1.3.0"},

External Transmission

Medium

• Category: Data Exfiltration
• Confidence: 60% confidence

Finding

Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.

Content

Scanner excerpt · SKILL.md (reported line 111)May include surrounding context.

python

import os, requests

response = requests.post(
    "https://api.jpverify.com/v1/jp/invoice-registrations/verify",
    headers={"Authorization": f"Bearer {os.environ['JPVERIFY_API_KEY']}",
             "X-JPVerify-Client": "jp-invoice-number-check/1.3.0"},

External Transmission

Medium

• Category: Data Exfiltration
• Confidence: 60% confidence

Finding

Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.

Content

Scanner excerpt · references/examples.md (reported line 41)May include surrounding context.

python

import os, requests

response = requests.post(
    "https://api.jpverify.com/v1/jp/invoices/check-issuer",
    headers={"Authorization": f"Bearer {os.environ['JPVERIFY_API_KEY']}",
             "X-JPVerify-Client": "jp-invoice-number-check/1.3.0"},

External Transmission

Medium

• Category: Data Exfiltration
• Confidence: 60% confidence

Finding

Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.

Content

Scanner excerpt · references/examples.md (reported line 87)May include surrounding context.

python

import os, requests

response = requests.post(
    "https://api.jpverify.com/v1/jp/invoices/check-issuer-batch",
    headers={"Authorization": f"Bearer {os.environ['JPVERIFY_API_KEY']}",
             "X-JPVerify-Client": "jp-invoice-number-check/1.3.0"},

External Transmission

Medium

• Category: Data Exfiltration
• Confidence: 50% confidence

Finding

Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.

Content

Scanner excerpt · SKILL.md (reported line 131)May include surrounding context.

-d '{"registration_number": "T1013301046627", "response_language": "both"}'

text

Full SDK examples (Python `x402`, JavaScript `@x402/fetch`): https://api.jpverify.com/docs/x402

## Limits and privacy / 制限とプライバシー

External Transmission

Medium

• Category: Data Exfiltration
• Confidence: 50% confidence

Finding

Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.

Content

Scanner excerpt · SKILL.md (reported line 138)May include surrounding context.

md

- Results are a **public-registry pre-check** with the source and as-of date of the data. They are not KYB, AML or sanctions screening, and not legal, tax or accounting advice. A "not found" does not mean the entity does not exist or is risky.
- If `manual_review_required` is true or a status is ambiguous, show the evidence to the user and let them decide; do not decide on their behalf.
- Only send data the user is entitled to process. JPVerify takes fields, not files; do not send personal details (names, phone numbers, e-mail addresses) that a check does not need.
- Docs: API key https://api.jpverify.com/docs/api-key · x402 https://api.jpverify.com/docs/x402 · terms https://api.jpverify.com/en/terms · privacy https://api.jpverify.com/en/privacy

External Transmission

Medium

• Category: Data Exfiltration
• Confidence: 50% confidence

Finding

Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.

Content

Scanner excerpt · SKILL.md (reported line 138)May include surrounding context.

md

- Results are a **public-registry pre-check** with the source and as-of date of the data. They are not KYB, AML or sanctions screening, and not legal, tax or accounting advice. A "not found" does not mean the entity does not exist or is risky.
- If `manual_review_required` is true or a status is ambiguous, show the evidence to the user and let them decide; do not decide on their behalf.
- Only send data the user is entitled to process. JPVerify takes fields, not files; do not send personal details (names, phone numbers, e-mail addresses) that a check does not need.
- Docs: API key https://api.jpverify.com/docs/api-key · x402 https://api.jpverify.com/docs/x402 · terms https://api.jpverify.com/en/terms · privacy https://api.jpverify.com/en/privacy

External Transmission

Medium

• Category: Data Exfiltration
• Confidence: 50% confidence

Finding

Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.

Content

Scanner excerpt · SKILL.md (reported line 138)May include surrounding context.

md

- Results are a **public-registry pre-check** with the source and as-of date of the data. They are not KYB, AML or sanctions screening, and not legal, tax or accounting advice. A "not found" does not mean the entity does not exist or is risky.
- If `manual_review_required` is true or a status is ambiguous, show the evidence to the user and let them decide; do not decide on their behalf.
- Only send data the user is entitled to process. JPVerify takes fields, not files; do not send personal details (names, phone numbers, e-mail addresses) that a check does not need.
- Docs: API key https://api.jpverify.com/docs/api-key · x402 https://api.jpverify.com/docs/x402 · terms https://api.jpverify.com/en/terms · privacy https://api.jpverify.com/en/privacy

External Transmission

Medium

• Category: Data Exfiltration
• Confidence: 50% confidence

Finding

Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.

Content

Scanner excerpt · SKILL.md (reported line 138)May include surrounding context.

md

- Results are a **public-registry pre-check** with the source and as-of date of the data. They are not KYB, AML or sanctions screening, and not legal, tax or accounting advice. A "not found" does not mean the entity does not exist or is risky.
- If `manual_review_required` is true or a status is ambiguous, show the evidence to the user and let them decide; do not decide on their behalf.
- Only send data the user is entitled to process. JPVerify takes fields, not files; do not send personal details (names, phone numbers, e-mail addresses) that a check does not need.
- Docs: API key https://api.jpverify.com/docs/api-key · x402 https://api.jpverify.com/docs/x402 · terms https://api.jpverify.com/en/terms · privacy https://api.jpverify.com/en/privacy

External Transmission

Medium

• Category: Data Exfiltration
• Confidence: 50% confidence

Finding

Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.

Content

Scanner excerpt · references/examples.md (reported line 3)May include surrounding context.

md

# jp-invoice-number-check — request examples

Set `JPVERIFY_API_KEY` (create one at https://www.jpverify.com/signup?ref=jp-invoice-number-check). Without a key the API answers HTTP 402 with the x402 price; see https://api.jpverify.com/docs/x402 for x402 SDK code.

## `POST /v1/jp/invoice-registrations/verify` — $0.01

External Transmission

Medium

• Category: Data Exfiltration
• Confidence: 60% confidence

Finding

Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.

Content

Scanner excerpt · references/examples.md (reported line 8)May include surrounding context.

POST /v1/jp/invoice-registrations/verify — $0.01

bash

curl -X POST https://api.jpverify.com/v1/jp/invoice-registrations/verify \
  -H "Authorization: Bearer $JPVERIFY_API_KEY" \
  -H "X-JPVerify-Client: jp-invoice-number-check/1.3.0" \
  -H "Content-Type: application/json" \

External Transmission

Medium

• Category: Data Exfiltration
• Confidence: 50% confidence

Finding

Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.

Content

Scanner excerpt · references/examples.md (reported line 8)May include surrounding context.

POST /v1/jp/invoice-registrations/verify — $0.01

bash

curl -X POST https://api.jpverify.com/v1/jp/invoice-registrations/verify \
  -H "Authorization: Bearer $JPVERIFY_API_KEY" \
  -H "X-JPVerify-Client: jp-invoice-number-check/1.3.0" \
  -H "Content-Type: application/json" \

External Transmission

Medium

• Category: Data Exfiltration
• Confidence: 50% confidence

Finding

Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.

Content

Scanner excerpt · references/examples.md (reported line 19)May include surrounding context.

md

import os, requests

response = requests.post(
    "https://api.jpverify.com/v1/jp/invoice-registrations/verify",
    headers={"Authorization": f"Bearer {os.environ['JPVERIFY_API_KEY']}",
             "X-JPVerify-Client": "jp-invoice-number-check/1.3.0"},
    json={"registration_number": "T1013301046627", "response_language": "both"},

External Transmission

Medium

• Category: Data Exfiltration
• Confidence: 50% confidence

Finding

Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.

Content

Scanner excerpt · references/examples.md (reported line 54)May include surrounding context.

POST /v1/jp/invoice-registrations/verify-batch — $0.008 per item

bash

curl -X POST https://api.jpverify.com/v1/jp/invoice-registrations/verify-batch \
  -H "Authorization: Bearer $JPVERIFY_API_KEY" \
  -H "X-JPVerify-Client: jp-invoice-number-check/1.3.0" \
  -H "Content-Type: application/json" \