League of Legends MCP Server

LoL get runes

lol_get_runes

Retrieve rune trees including keystones, minor runes, and descriptions. Filter by tree name or patch version.

Instructions

Get rune trees with keystones, minor runes, descriptions

Tool call template

This tool declares no required parameters. Add optional parameters from the input schema as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {},
    "name": "lol_get_runes"
  }
}

Input Schema

Name	Required	Description	Default
`group`	No	Filter by tree name (Precision, Domination, Sorcery, Resolve, Inspiration)
`patch`	No	Patch version (default: latest)

Schema Changelog

Changes observed during successful MCP inspections.

First observedv1.1.1Jul 29, 2026

TDQS

B3.2/5.0

Behavior2/5

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

No annotations are provided, so the description carries full burden for behavioral transparency. It only states the basic action ('get') and result content, but does not disclose whether it is destructive, requires authentication, has rate limits, or any side effects. For a data retrieval tool, this is minimally acceptable but leaves many safety aspects implicit.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, front-loaded sentence that conveys essential information. It is efficient with no wasted words. A slightly structured format (e.g., listing returned data) could improve readability, but current form is adequate.

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?

Given no output schema, the description reasonably explains return values ('rune trees with keystones, minor runes, descriptions'). The optional parameters are well-documented in the schema. For a simple data retrieval tool with low complexity, the description is sufficiently complete to guide correct invocation.

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?

The input schema covers both parameters with descriptions (e.g., 'Filter by tree name' for group). The description adds context about what the tool returns (rune trees, keystones, etc.), which complements the schema. With 100% schema coverage, the description adds meaningful extra clarity.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the tool retrieves rune trees including keystones, minor runes, and descriptions. It uses a specific verb ('Get') and resource ('rune trees'). No sibling tools directly overlap with rune data, so differentiation is not needed.

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 provides no guidance on when to use this tool versus alternatives. There is no mention of prerequisites, context, or exclusions. The agent must infer usage from the tool name and description alone.

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