tld-list-mcp

Compare registrars

compare_registrars

Read-onlyIdempotent

Compare registration, renewal, and transfer prices for a single TLD across selected registrar IDs, including missing prices, promotions, terms, and notes.

Instructions

Compare documented registration, renewal, and/or transfer pricing for one TLD at selected TLD-List registrar IDs, including missing prices, promotions, terms, and notes.

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": {
      "tld": "<tld>",
      "registrars": "<registrars>"
    },
    "name": "compare_registrars"
  }
}

Input Schema

Name	Required	Description	Default
`tld`	Yes
`priceTypes`	No
`registrars`	Yes

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.1.3Oct 1, 2026

TDQS

B3.2/5.0

Behavior3/5

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

Annotations already declare readOnly, idempotent, openWorld and non-destructive, covering the safety profile. The description adds useful behavioral context about what is returned (missing prices, promotions, terms, notes), which matters because no output schema exists, but says nothing about freshness or coverage limits of the pricing 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?

One dense sentence, front-loaded with the verb and the compared dimensions, with no filler. The trailing list of included data is a bit packed but each item earns its place given the absence of an output schema.

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?

With no output schema, the description usefully enumerates the returned data elements, but leaves gaps on parameter defaults, limits, and registrar ID format, and offers no routing guidance among the pricing/cost siblings.

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?

Schema coverage is 0%, so the description must carry the parameter burden. It does map the price types (registration/renewal/transfer implied by wording) to priceTypes and 'registrar IDs' to registrars, but omits the default price-type set, the 50-registrar cap, and ID format expectations.

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?

States a specific verb (Compare) and resource (registration, renewal, transfer pricing) with clear scope: one TLD across selected registrar IDs. This implicitly separates it from compare_tlds, which operates on the TLD axis, though no sibling is named explicitly.

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 says what is compared but gives no when-to-use guidance and names no alternatives, despite siblings like cheapest_registrar, compare_tlds, and calculate_domain_cost that could be confused with it.

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

Deploy Server