expense-tracker-mcp

add_expense

Log a single expense by specifying date, amount, and category, with optional note and subcategory, so your personal expense records stay accurate.

Instructions

Record a single expense.

Pass the user's local date -- the server does not infer 'today', because its clock is UTC and would log the wrong day either side of midnight.

Input Schema

TableJSON Schema

Name	Required	Description
`date`	Yes	Date the money was spent, YYYY-MM-DD.
`note`	No	Optional free-text note.
`amount`	Yes	Amount spent. Must be greater than zero.
`category`	Yes	Top-level category, e.g. 'food'. Must be a known category.
`subcategory`	No	Optional subcategory, e.g. 'groceries'.

Output Schema

TableJSON Schema

Name	Required	Description	Default
No arguments

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.1.0Sep 4, 2026

TDQS

A4.2/5.0

Behavior4/5

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 discloses a subtle, high-impact behavior: the server uses UTC and will not infer today, so the client must pass the user's local date. It does not overstate side effects, but 'record' clearly signals creation.

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 with no filler. The essential behavioral warning about UTC is front-loaded in the second sentence and directly actionable.

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 a simple create operation with a full output schema and complete parameter documentation, the description covers the key pitfall an agent would likely miss. It does not mention category validation or sibling alternatives, but the schema states 'Must be a known category' and sibling names are self-explanatory.

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

Parameters4/5

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

Schema description coverage is 100%, so the baseline is 3. The description adds real value for the date parameter by explaining why the caller must supply the local date and how the server's UTC clock could cause errors. It does not need to repeat the other parameters since the schema already documents them fully.

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 opens with 'Record a single expense,' which is a specific verb, resource, and scope. This makes it immediately distinct from siblings like list_expenses, delete_expense, and summarize.

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 wording implies when to use the tool, but it does not explicitly contrast it with alternatives or state when not to use it. The date guidance is operational context, not a when-to-use vs. alternative boundary.

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

Deploy Server