Mempool MCP Server

get-recommended-fees

Retrieve optimal Bitcoin transaction fees based on current network conditions to ensure timely confirmations.

Instructions

Get recommended fees for Bitcoin

Input Schema

TableJSON Schema

Name	Required	Description	Default
No arguments

Implementation Reference

src/interface/controllers/FeesToolsController.ts:15-32 (registration)

Registers the 'get-recommended-fees' tool with the MCP server, including name, description, and an inline async handler that fetches and returns formatted fees as text content.

private registerGetRecommendedFeesHandler(): void {
  this.server.tool(
    "get-recommended-fees",
    "Get recommended fees for Bitcoin",
    async () => {
      const recommendedText = await this.feesService.getRecommended();

      return {
        content: [
          {
            type: "text",
            text: recommendedText,
          },
        ],
      };
    }
  );
}

src/domain/models/responses/fees/IFeesRecommendedResponse.ts:1-7 (schema)
TypeScript interface defining the response structure for recommended Bitcoin fees data.
```
export interface IFeesRecommendedResponse {
  fastestFee: number;
  halfHourFee: number;
  hourFee: number;
  economyFee: number;
  minimumFee: number;
}
```

src/application/services/FeesService.ts:9-15 (helper)

Service method that retrieves raw recommended fees data via request service and formats it into a human-readable string.

async getRecommended(): Promise<string> {
  const feesRecommendedData = await this.requestService.getFeesRecommended();
  return formatResponse<IFeesRecommendedResponse>(
    "Bitcoin Fees Recommended",
    feesRecommendedData
  );
}

src/infrastructure/services/requests/FeesRequestService.ts:7-11 (helper)
Infrastructure method that makes an API request to the 'fees/recommended' endpoint to fetch the fees data.
```
async getFeesRecommended(): Promise<IFeesRecommendedResponse | null> {
  return this.client.makeRequest<IFeesRecommendedResponse>(
    "fees/recommended"
  );
}
```

Schema Changelog

Changes observed during successful MCP inspections.

First observedAug 15, 2025

TDQS

B3.4/5.0

Behavior2/5

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

No annotations provided and the description does not disclose behavioral traits such as data source or side effects; even for a simple get, more transparency is needed.

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?

Extremely concise, one sentence, front-loaded with the key verb and resource, no wasted words.

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?

For a parameterless tool with no output schema, the description is largely complete, though it could mention return format or basis of fees.

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?

No parameters exist, so schema coverage is 100%. The description adds no parameter meaning, but baseline is 3 for high coverage.

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 states the verb 'Get' and the resource 'recommended fees for Bitcoin', distinguishing it from siblings like get-block and get-ping.

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?

No guidance on when to use this tool vs alternatives; the description is minimal without context.

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