MF Invoice MCP

mf_create_billing

Create invoices compliant with Japan's invoice system by specifying partner details, billing dates, and itemized charges with tax classifications.

Instructions

インボイス制度対応の請求書を作成します

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": {
      "partner_id": "<partner_id>",
      "billing_date": "<billing_date>",
      "items": "<items>"
    },
    "name": "mf_create_billing"
  }
}

Input Schema

Name	Required	Description
`partner_id`	Yes	取引先ID（必須）
`title`	No	請求書タイトル
`memo`	No	メモ
`payment_condition`	No	支払条件
`billing_date`	Yes	請求日（YYYY-MM-DD）
`due_date`	No	支払期限（YYYY-MM-DD）
`sales_date`	No	売上日（YYYY-MM-DD）
`items`	Yes	明細行

Schema Changelog

Changes observed during successful MCP inspections.

First observedv1.0.1Feb 1, 2026

TDQS

C2.9/5.0

Behavior2/5

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It states the tool creates invoices but doesn't mention whether this is a write operation (implied), what permissions are needed, if it's idempotent, or what happens on success/failure (e.g., returns an ID or error). For a creation tool with zero annotation coverage, this is a significant gap in transparency.

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

Conciseness5/5

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

The description is a single, efficient sentence in Japanese that front-loads the core purpose. It wastes no words and directly states what the tool does. Every part of the sentence earns its place by specifying the action and compliance context.

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

Completeness2/5

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

Given the complexity (8 parameters, nested items array, no output schema, and no annotations), the description is incomplete. It doesn't explain the invoice system context, what 'インボイス制度対応' entails, or the expected output (e.g., a billing ID or confirmation). For a creation tool with significant input structure, more context is needed to guide the agent effectively.

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?

The description adds no parameter-specific information beyond what's in the schema. However, schema description coverage is 100%, with all 8 parameters and nested items well-documented in Japanese (e.g., partner_id as '取引先ID（必須）', excise enum explained). The baseline is 3 when the schema does the heavy lifting, and the description doesn't compensate with additional context like format examples or business rules.

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?

The description clearly states the tool's purpose: 'インボイス制度対応の請求書を作成します' (creates invoices compliant with the invoice system). It specifies the verb '作成します' (creates) and resource '請求書' (invoices), and distinguishes from siblings like mf_create_quote or mf_create_delivery_slip by focusing on billing. However, it doesn't explicitly differentiate from mf_create_billing_from_quote or mf_convert_quote_to_billing, which are also billing-related.

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

Usage Guidelines2/5

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

The description provides no guidance on when to use this tool versus alternatives. It doesn't mention prerequisites (e.g., authentication), when to choose this over mf_create_billing_from_quote, or any constraints (e.g., only for new invoices). Without such context, the agent must infer usage from the tool name and schema alone.

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