MTG Bench

rate_deck

Read-only

Assess a Commander deck's official WotC bracket (1-5). Returns deterministic signals (Game Changers from WotC's curated list, mass land denial, tutors, fast mana, free interaction), a bracket FLOOR from the official decision tree, and the rubric — then YOU finish the assessment: check for compact two-card win combos and weigh soft signals per the assessmentGuidance, and state the final bracket with evidence.

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": {
      "cards": "<cards>"
    },
    "name": "rate_deck"
  }
}

Input Schema

Name	Required	Description	Default
`cards`	Yes
`commander`	No

Output Schema

Name	Required	Description	Default
`deck`	Yes
`notes`	No
`rubric`	Yes
`signals`	Yes
`earlyCombo`	No
`bracketFloor`	Yes
`unknownCards`	No
`combosPresent`	No
`assessmentGuidance`	Yes
`bracketFloorReason`	Yes

Schema Changelog

Changes observed during successful MCP inspections.

First observedAug 9, 2026

TDQS

A4.4/5.0

Behavior5/5

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

Beyond the readOnlyHint annotation, the description discloses the exact deterministic signals returned, the bracket floor, the rubric, and the fact that the tool is intentionally incomplete—requiring the agent to complete the assessment. This goes well beyond annotations, revealing the tool's role and limitations.

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, front-loaded with the purpose, then dense with high-value behavioral details. No filler or redundancy. The structure flows logically: what it does, what it returns, what the agent must do.

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

Completeness5/5

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

The description fully captures the tool's scope: its inputs are implicit but the behavior and output are thoroughly described. It even tells the agent the next steps (checking combos, weighing soft signals). With an output schema present, return format is covered. Only parameter semantics are weak, but that is captured in a separate dimension.

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

Parameters2/5

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

The description makes no mention of the 'cards' or 'commander' parameters, leaving all meaning to the schema. With 0% schema description coverage, the agent receives no guidance on how to format the deck input or whether commander is optional. The description fails to compensate for the schema's lack of examples.

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 begins with a specific verb-resource pair: 'Assess a Commander deck's official WotC bracket (1-5).' It clearly distinguishes this from siblings like deck_stats or find_combos by focusing on deterministic signals and the official decision tree. The purpose is unambiguous and specific.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines4/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description clearly implies the tool is used to start a bracket assessment, and it provides explicit context on how to proceed: the tool returns a floor and rubric, and the agent must finish the assessment by checking combos and soft signals. It does not explicitly state alternatives or exclusions, but the workflow is well-defined.

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

All MTG Bench tools Inspect

Try in Browser

One endpoint for every MCP toolRayrun runs every MCP server behind one URL and holds the credentials. Each call is decided per client, tool, and argument, then recorded.ray.runAd

Glama MCP Gateway

Add one secure layer between your agents and this server.

Resources

Need Help?