LunchMoney MCP Server

update_category

Idempotent

Update an existing category or category group in LunchMoney: rename, archive, move between groups, adjust budget settings, and replace child categories for groups.

Instructions

Update properties for an existing category or category group. For category groups, supplying children replaces the group's full child list. Cannot be used to convert between category and category group.

Input Schema

TableJSON Schema

Name	Required	Description
`name`	No	New name. 1-100 characters.
`archived`	No
`children`	No	Only valid for category groups. Replaces the group's full children list. Existing IDs (numbers) keep/move categories; strings create new sub-categories.
`group_id`	No	Move this category into the specified category group, or null to remove from any group.
`is_income`	No
`categoryId`	Yes	Id of the category or category group to update.
`description`	No	New description. Up to 200 characters.
`exclude_from_budget`	No
`exclude_from_totals`	No

Schema Changelog

Changes observed during successful MCP inspections.

Addedv1.0.3Jun 3, 2026
Removedv1.0.2May 20, 2026

Changed13 schema fields changedv1.0.1May 13, 2026

addedInput schema / $schema

Added value: +"http://json-schema.org/draft-07/schema#"

addedInput schema / additionalProperties
```
Added value: +false
```
addedInput schema / properties / archived
```
Added value: +{
+  "type": "boolean"
+}
```

addedInput schema / properties / categoryId

Added value: +{
+  "description": "Id of the category or category group to update.",
+  "type": "number"
+}

addedInput schema / properties / children

Added value: +{
+  "description": "Only valid for category groups. Replaces the group's full children list. Existing IDs (numbers) keep/move categories; strings create new sub-categories.",
+  "items": {
+    "type": [
+      "number",
+      "string"
+    ]
+  },
+  "type": "array"
+}

addedInput schema / properties / description

Added value: +{
+  "description": "New description. Up to 200 characters.",
+  "maxLength": 200,
+  "type": "string"
+}

addedInput schema / properties / exclude_from_budget
```
Added value: +{
+  "type": "boolean"
+}
```
addedInput schema / properties / exclude_from_totals
```
Added value: +{
+  "type": "boolean"
+}
```

addedInput schema / properties / group_id

Added value: +{
+  "description": "Move this category into the specified category group, or null to remove from any group.",
+  "type": [
+    "number",
+    "null"
+  ]
+}

removedInput schema / properties / input

Removed value: -{
-  "additionalProperties": false,
-  "properties": {
-    "archived": {
-      "default": false,
-      "description": "Whether or not category should be archived.",
-      "type": "boolean"
-    },
-    "categoryId": {
-      "description": "Id of the category or category group to update. Execute the get_all_categories tool first, to get the category ids.",
-      "type": "string"
-    },
-    "description": {
-      "default": "",
-      "description": "Description of category. Must be less than 140 characters.",
-      "type": "string"
-    },
-    "exclude_from_budget": {
-      "default": false,
-      "description": "Whether or not transactions in this category should be excluded from budgets.",
-      "type": "boolean"
-    },
-    "exclude_from_totals": {
-      "default": false,
-      "description": "Whether or not transactions in this category should be excluded from calculated totals.",
-      "type": "boolean"
-    },
-    "group_id": {
-      "description": "Assigns the newly-created category to an existing category group.",
-      "type": "number"
-    },
-    "is_income": {
-      "default": false,
-      "description": "Whether or not transactions in this category should be treated as income.",
-      "type": "boolean"
-    },
-    "name": {
-      "description": "Name of category. Must be between 1 and 40 characters.",
-      "type": "string"
-    }
-  },
-  "required": [
-    "name",
-    "categoryId"
-  ],
-  "type": "object"
-}

addedInput schema / properties / is_income
```
Added value: +{
+  "type": "boolean"
+}
```

addedInput schema / properties / name

Added value: +{
+  "description": "New name. 1-100 characters.",
+  "maxLength": 100,
+  "minLength": 1,
+  "type": "string"
+}

changedInput schema / required

Previous value: -[
-  "input"
-]New value: +[
+  "categoryId"
+]

First observedv1.0.0Sep 25, 2025

TDQS

A4/5.0

Behavior4/5

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

Beyond the idempotentHint annotation, the description discloses key behaviors: 'supplying children replaces the group's full child list' and 'Cannot be used to convert between category and category group.' This adds useful context for safe invocation.

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 two sentences, front-loaded with the core action, and every sentence adds value. No unnecessary words.

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

Completeness4/5

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

For an update tool with 9 parameters and no output schema, the description covers the main constraints and behaviors. It lacks return value details but is otherwise complete for an update operation.

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 some value by explaining the children parameter behavior, but overall parameter semantics rely heavily on the input schema (56% coverage). The description does not compensate for undocumented parameters sufficiently.

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 clearly states the tool updates an existing category or category group, with a specific verb and resource. It distinguishes between updating a category and a category group, and among siblings like create_category and delete_category, its purpose is evident.

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 implies usage by stating what the tool does but does not explicitly guide when to use it over alternatives like create_category or delete_category. No exclusions or when-not-to-use guidance is provided.

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

Deploy Server

update_category

Instructions

Input Schema

Schema Changelog

TDQS

Other Tools