draftkingsapi-mcp

Arbitrage and middles

get_arbitrage

Read-only

Find cross-book arbitrage and middle opportunities by comparing sportsbook odds and filtering by league, market type, minimum profit, and result limit.

Instructions

Arbitrage and middle opportunities across books. Needs DRAFTKINGS_API_KEY (free key, no card, at https://draftkingsapi.com/sign-up).

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": "get_arbitrage"
  }
}

Input Schema

Name	Required	Description
`task`	No	Optional: the user's task in one plain sentence, nothing personal. Helps the API return what fits.
`type`	No
`limit`	No	Rows to return, at most 200.
`league`	No
`min_profit`	No
`market_type`	No

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.1.0Nov 15, 2026

TDQS

C2.9/5.0

Behavior3/5

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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety and external-data profile is known. The description earns credit for disclosing the DRAFTKINGS_API_KEY authentication requirement and where to obtain it, which annotations do not cover. It says nothing about freshness of odds, rate limits, or what a 'middle' entails in the returned data.

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?

Two short sentences with the purpose front-loaded and the prerequisite immediately after; no filler. The signup URL makes the second sentence slightly operational rather than descriptive, but it is still useful information.

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

Completeness2/5

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

For a six-parameter, no-output-schema tool that computes arbitrage opportunities, the description omits what the results look like (profit percentages, book/leg pairings) and leaves most filters unexplained. An agent could call it, but only by guessing at min_profit semantics and what rows will contain.

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?

Schema description coverage is only 33% across six parameters, so the description is expected to compensate and does not. The words 'arbitrage' and 'middles' map loosely to the type enum, but min_profit, market_type, league, limit, and task receive no explanation of meaning, units, or effect.

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 names a specific resource — arbitrage and middle opportunities across books — which is more precise than the title alone and matches the tool name. It does not, however, distinguish this from nearby siblings such as get_ev or get_compare, so an agent must infer the boundary.

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?

There is no guidance on when to choose this over get_ev, get_compare, or get_odds, nor any exclusion or scenario framing. The only conditional content is a prerequisite (API key), not a usage rule.

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