Formosa MCP

invoice_check

Check a Taiwan invoice number for lottery winnings across the latest draw and prior claimable period. For 3–7 digit numbers, verify sixth-prize eligibility.

Instructions

統一發票對獎；未指定期別時檢查最新一期與仍可領獎的前一期。Check a Taiwan invoice number; 3–7 digits only check sixth prizes.

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "number": "<number>"
    },
    "name": "invoice_check"
  }
}

Input Schema

Name	Required	Description	Default
`number`	Yes
`period`	No

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.2.0Nov 6, 2026

TDQS

B3.4/5.0

Behavior3/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations exist, so the description carries the full disclosure burden. It does add two useful behavioral facts — the default period scope and the "3–7 digits only check sixth prizes" constraint — but says nothing about what the response contains, whether a non-matching number returns an error or a negative result, or any rate limits.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Two compact clauses, front-loaded with the core action, with no filler. The bilingual duplication adds length but serves the tool's Taiwan-specific audience and stays brief.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness3/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a simple two-parameter lookup this is close to adequate, and default-period handling is a genuinely necessary detail. But with no annotations and no output schema, the agent still lacks any picture of the return shape or how a losing number is reported.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 0%, and the two parameters (number, period) are bare strings in the schema. The description partially compensates by explaining the period default and hinting at digit semantics for number, but it does not specify an accepted period format (e.g., 11305 vs 2024-05) or whether dashes/spaces are allowed in number.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

"Check a Taiwan invoice number" states a specific verb and resource, and the Chinese clause names the domain (統一發票對獎) unambiguously. It is clearly distinct from the sibling invoice_get_winning_numbers, though it never names that sibling explicitly.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines3/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description covers default behavior when period is omitted (latest period plus the prior period still claimable), which is real usage guidance. However, it never states when to use this tool versus invoice_get_winning_numbers, nor any prerequisite such as obtaining the winning numbers first.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

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