ynab-mcp

get_spending_by_category

Retrieve monthly spending by category, comparing budget vs actual, sorted by highest spend, with balance and percentage of total.

Instructions

Get per-category spending breakdown for a month, with budget vs actual comparison.

Returns categories sorted by spending (highest first), grouped by category group, with budgeted, spent, balance, and percentage of total spending.

Args: plan_id: The plan ID (use list_plans to find available IDs) month: Month in YYYY-MM-DD format (first of month, e.g. '2026-03-01') or 'current'

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": {
      "plan_id": "<plan_id>"
    },
    "name": "get_spending_by_category"
  }
}

Input Schema

Name	Required	Description	Default
`month`	No		current
`plan_id`	Yes

Output Schema

Name	Required	Description	Default
`result`	Yes

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.1.0Oct 7, 2026

TDQS

A4.4/5.0

Behavior3/5

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

No annotations are provided, so the description carries the full burden. It explains the return structure (sorted, grouped, fields) but does not disclose any side effects, permissions, or rate limits. While adequate for a read operation, it could be more comprehensive.

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 concise with a clear purpose line, a summary of return format, and brief parameter explanations. No wasted words.

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

Completeness5/5

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

Given the presence of an output schema (not shown but signaled), the description provides sufficient context about the tool's behavior and parameters. It covers all necessary aspects for an agent to use it correctly.

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

Parameters5/5

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

Schema coverage is 0%, but the description adds significant value: it explains that plan_id comes from list_plans and specifies the month format including the 'current' option. This goes well beyond the bare schema.

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

Purpose5/5

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

The description specifies a 'per-category spending breakdown' with 'budget vs actual comparison' and details the sorted, grouped return format. It clearly distinguishes from siblings like 'get_category' or 'get_transactions_by_category'.

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

Usage Guidelines4/5

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

The description provides context by mentioning 'use list_plans to find available IDs' and specifying the month format, but does not explicitly state when to use this tool over alternatives like 'get_transactions_by_category'.

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

Deploy Server