YNAB MCP Server

Get Category

get_category

Read-onlyIdempotent

Retrieve a category's full details for the current month, including goal targets and funding progress. Use this read-only tool to inspect category goals.

Instructions

Get one category's full detail for the current month, including goal/target fields (type, target amount, funding progress). Read-only. Use for goal inspection; for a past or future month's numbers use get_month_category instead.

Input Schema

TableJSON Schema

Name	Required	Description	Default
`budgetId`	No	Budget ID (uses default if not provided)
`categoryId`	Yes	Category ID

Output Schema

TableJSON Schema

Name	Required	Description	Default
`result`	Yes

Schema Changelog

Changes observed during successful MCP inspections.

Changed1 schema field changedv5.4.0Sep 15, 2026
- removedOutput schema / properties / result / description
```
Removed value: -"Structured result returned by Get Category."
```

Changed1 schema field changedv5.1.1Jul 21, 2026

changedOutput schema / (root)

Previous value: -nullNew value: +{
+  "$schema": "http://json-schema.org/draft-07/schema#",
+  "additionalProperties": false,
+  "properties": {
+    "result": {
+      "description": "Structured result returned by Get Category."
+    }
+  },
+  "required": [
+    "result"
+  ],
+  "type": "object"
+}

First observedv2.0.0May 28, 2026

TDQS

A4.5/5.0

Behavior4/5

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

Annotations already cover read-only/idempotent/non-destructive behaviorza. The description adds non-obvious context: the tool is scoped to the current month and includes goal/target fields, which is useful beyond what annotations state.

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?

Two concise sentences, front-loaded with the operation and scope, followed by routing guidance. No filler; the redundancy of 'Read-only' with annotations is minor and does not hurt clarity.

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?

For a read-only single-resource lookup with full schema coverage and an output schema, this description provides the necessary scope and routing context. Nothing critical is missing for correct invocation.

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 100%, so the schema already documents both budgetId and categoryId. The description adds contextual meaning about current-month data but no additional parameter-level format or behavior details.

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?

States it retrieves one category's full detail for the current monthches, explicitly mentioning goal/target fields. It clearly identifies the resource and scope, and differentiates from get_month_category.

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

Usage Guidelines5/5

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

Explicitly says 'Use for goal inspection' and directs past/future month queries to get_month_category instead. This gives the agent a clear selection criterion and alternative.

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