o3de-mcp

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get_cvar

Retrieve the current value of any O3DE console variable (CVAR) to inspect runtime settings. Use this to debug or configure engine parameters directly.

Instructions

Get the value of an O3DE console variable (CVAR).

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": {
      "name": "<name>"
    },
    "name": "get_cvar"
  }
}

Input Schema

Name	Required	Description	Default
`name`	Yes

Output Schema

Name	Required	Description	Default
`result`	Yes

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.3.0Sep 5, 2026

TDQS

B3.3/5.0

Behavior2/5

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It only says 'Get the value', which implies a read operation, but it does not disclose behavior for missing CVARs, types of returned values, or any error conditions. For a tool with no annotation safety hints, this is a notable gap.

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 a single, focused sentence with no filler. The key action and resource are both front-loaded, making it easy for an agent to parse quickly.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness3/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

The tool is simple, with one parameter and an output schema available, so the description does not need to explain return structure. However, it lacks behavioral context such as error handling, side effects, or any usage caveats, which matters because no annotations are present to cover these concerns.

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

Parameters3/5

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

The input schema only provides a required string parameter named 'name' with no description, and schema description coverage is 0%. The tool description clarifies that 'name' refers to an O3DE console variable, which adds meaning, but it does not explain naming conventions, valid formats, or whether names are case-sensitive. It minimally compensates for the schema gap.

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 states a specific verb ('Get') and resource ('value of an O3DE console variable (CVAR)'), making the tool's purpose immediately clear. It also naturally contrasts with the sibling 'set_cvar', so an agent can distinguish the two without opening schemas.

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 gives no guidance about when to use this tool versus alternatives such as 'set_cvar' or 'run_console_command'. There are no explicit conditions, exclusions, or references to sibling tools, leaving the agent to infer usage.

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

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