Warcraft 3 MCP Server

Overview Schema Source Related Servers Discussions Admin

Modify placed unit(s)

wc3_modify_unit

Change unit properties like position, ownership, scale, facing, type, hitpoints, and mana in a Warcraft III map. Output to a specified or automatically named file.

Instructions

Change fields on the unit(s) matched by select — move them, re-own them, rescale, re-face, swap type, or set HP/mana. Saves to outPath, or ".edited." beside the source (pass the source path to overwrite in place).

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": {
      "mapPath": "<mapPath>",
      "select": "<select>",
      "set": "<set>"
    },
    "name": "wc3_modify_unit"
  }
}

Input Schema

Name	Required	Description
`mapPath`	Yes	Absolute path to the source .w3x/.w3m map file
`select`	Yes	Which unit(s) to target — provide at least one field; `type` can match many
`set`	Yes	Fields to change on every matched unit
`outPath`	No	Output map path. Defaults to "<map>.edited.<ext>".

Schema Changelog

Changes observed during successful MCP inspections.

First observedv1.0.0Jun 22, 2026

TDQS

A4.2/5.0

Behavior4/5

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

Discloses output behavior (saves to outPath or default edited file, can overwrite in place). No annotations exist, so description carries full burden. Could mention error handling or irreversible changes, but current text is adequate.

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?

Two sentences, first covers purpose and operations, second covers output. Front-loaded, no wasted 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?

Description covers main behavior and output. With no output schema, a note on return value would help. Missing edge cases or error conditions, but overall sufficient for the tool's complexity.

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%, baseline 3. Description adds value by summarizing the types of changes (move, re-own, etc.) beyond the schema's per-field descriptions.

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 it modifies placed units with specific operations (move, re-own, rescale, etc.). It distinguishes from siblings like wc3_modify_doodad and wc3_delete_unit by focusing on unit fields.

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?

Usage is implied (modify existing units), but no explicit when-to-use or when-not-to-use compared to alternatives like wc3_place_unit or wc3_delete_unit. No context for prerequisites.

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