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get_exchange_rate

Retrieve the exchange rate between two tokens, showing how much of the destination token you receive for 1 unit of the source token.

Instructions

Get the exchange rate between two tokens. Returns the rate for swapping 1 unit of from_token to to_token.

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": {
      "from_token": "<from_token>",
      "to_token": "<to_token>"
    },
    "name": "get_exchange_rate"
  }
}

Input Schema

Name	Required	Description
`to_token`	Yes	Destination token address
`from_token`	Yes	Source token address
`to_decimals`	No	Decimals of destination token (default: 18)
`from_decimals`	No	Decimals of source token (default: 18)

Schema Changelog

Changes observed during successful MCP inspections.

First observedv1.0.0Aug 3, 2026

TDQS

A3.5/5.0

Behavior2/5

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

With no annotations provided, the description must carry the full burden of behavioral disclosure. It only adds the '1 unit' scaling detail; it does not explain whether the rate includes fees, is a mid-market price, or has other assumptions. This leaves important behavioral characteristics undisclosed.

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 two sentences, front-loads the main action, and includes no filler. Every phrase earns its place by clarifying the rate direction.

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?

This is a simple lookup tool with a well-specified schema, but no output schema is provided. The description does not specify the return format (e.g., integer vs decimal, precision), and lacks caveats such as live vs stale rates. Given the simplicity, it's adequate but leaves some gaps.

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 already describes all parameters with 100% coverage, so baseline is 3. The description adds directional meaning by specifying the rate is for swapping 1 unit of from_token to to_token, which clarifies how decimals and token addresses are used. This value bumps it above baseline.

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 identifies the tool as getting an exchange rate between two tokens, with a specific verb and resource. It also defines the rate as 'swapping 1 unit of from_token to to_token,' which distinguishes it from generic market data or swap quoting tools in the sibling list.

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 offers no guidance about when to use this tool versus alternative tools such as get_swap_quote or get_market. There is no mention of scenarios, limitations, or exclusions, so an agent has to infer fit from the name alone.

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