Modify existing RPG Maker MZ database records by specifying an entity type, ID, and the fields to change. Update only the attributes you provide; other values stay intact.
Update an existing entity. Only provided fields will be changed.
| Name | Required | Description | Default |
|---|---|---|---|
| id | Yes | Entity ID to update | |
| data | Yes | Fields to update (JSON object) | |
| entityType | Yes | Entity type |
Changes observed during successful MCP inspections.
v1.0.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full burden. It does disclose one genuinely useful behavioral trait — merge/PATCH semantics ('only provided fields will be changed') — but says nothing about permissions, whether entityType must match the stored entity, error behavior on unknown fields, or reversibility.
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?
Two short sentences, zero waste, with the action stated first and the partial-update constraint front-loaded immediately after. Nothing is padded or restated.
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?
This is a mutation tool with no annotations and no output schema, and its 'data' parameter accepts an arbitrary nested object whose valid fields are entity-type dependent. The description should cover permissions, the meaning of entityType relative to the target, and the response shape, but covers none of them.
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 coverage is 100%, so all three parameters are already documented in the schema, and the description adds no syntax or format detail. The free-form nested 'data' object whose valid keys depend on entityType is the main semantic gap, but with full schema coverage the baseline of 3 applies.
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?
States a specific verb (update) plus resource (entity) and adds the partial-update scope. The resource name distinguishes it from sibling mutators like update_map and update_event, but it never explicitly contrasts itself with create_entity/delete_entity, so it falls short of the 5 bar.
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?
No when-to-use guidance, no prerequisites, no alternatives named. The reader must infer from the sibling list that create_entity and delete_entity cover the other cases; the description itself offers no routing context.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.