Lunch Money MCP Server

updateTag

Modify an existing tag's name in your Lunch Money financial data to maintain accurate categorization and organization of transactions.

Instructions

Update an existing tag's name

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": {
      "id": "<id>",
      "name": "<name>"
    },
    "name": "updateTag"
  }
}

Input Schema

Name	Required	Description	Default
`id`	Yes
`name`	Yes

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.1.0Jan 28, 2026

TDQS

C2.8/5.0

Behavior2/5

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

With no annotations provided, the description carries full burden for behavioral disclosure. It states the tool updates a tag's name, implying a mutation operation, but doesn't disclose important traits like permission requirements, whether changes are reversible, potential side effects, or error conditions. The description is minimal and lacks behavioral context.

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 extremely concise with a single, direct sentence that states the core purpose without unnecessary words. It's front-loaded and wastes no space, making it efficient for quick understanding.

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 tool's mutation nature, lack of annotations, no output schema, and 0% schema description coverage, the description is incomplete. It doesn't address what happens after the update, potential constraints, or provide enough context for safe and effective use. The minimal description leaves significant gaps.

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

Parameters2/5

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

Schema description coverage is 0%, so the description must compensate for undocumented parameters. It mentions updating 'name' but doesn't explain the 'id' parameter or provide any semantic context for either parameter. The description adds minimal value beyond what's inferred from the schema structure alone.

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 action ('Update') and resource ('an existing tag's name'), making the purpose immediately understandable. It distinguishes from sibling tools like 'createTag' and 'deleteTag' by specifying modification rather than creation or deletion. However, it doesn't explicitly mention what 'tag' refers to in this context.

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., needing an existing tag ID), compare with similar tools like 'updateCategory', or indicate scenarios where this tool is appropriate versus when other tools might be better suited.

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