Update an existing expense record by providing its ID and any new values for date, amount, source, category, or description.
Update an existing expense record
| Name | Required | Description | Default |
|---|---|---|---|
| date | No | New date (YYYY-MM-DD) | |
| amount | No | New amount | |
| sourceId | No | New source ID | |
| categoryId | No | New category ID | |
| spendingId | Yes | Spending ID | |
| description | No | New description |
Changes observed during successful MCP inspections.
v1.0.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description carries the full burden of behavioral disclosure. It only says 'update' and gives no detail on partial update semantics, whether the record must exist, what happens on failure, or what the response contains. This is a significant gap for a mutation tool.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
The description is a single, short sentence with no filler or redundancy. It is appropriately front-loaded and contains the essential verb and object.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
The tool has 6 parameters, no output schema, and no annotations. The description does not explain whether all fields are optional for a partial update, whether spendingId must already exist, or how the updated record is returned. An agent would need to inspect the schema and infer behavior, which is risky for an update operation.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
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 each parameter. The description adds no additional meaning about date format, amount constraints, or the relationship between spendingId and the other fields, but the schema handles this adequately.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description 'Update an existing expense record' clearly states a specific verb and resource, and the word 'existing' helps distinguish it from create_spending. It does not go beyond that to explicitly differentiate from delete_spending or other update tools, but the action and target are unambiguous.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
There is no guidance about when to use this tool versus create_spending, delete_spending, or list_spendings. The word 'existing' weakly implies that the record must already exist, but no explicit conditions, prerequisites, or alternative recommendations are provided.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.