Railway MCP Server

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It states the tool checks domain availability but does not specify error handling, rate limits, authentication requirements, or what 'available for use' entails (e.g., registration status, cost implications). This leaves gaps in understanding the tool's behavior beyond its basic purpose.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is well-structured and front-loaded with the core purpose, followed by bullet points for usage guidelines and related tools. Every sentence earns its place by providing clear, actionable information without redundancy or unnecessary details.

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

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

Given the tool's low complexity (single parameter, no output schema) and the description's clear purpose and usage guidelines, it is mostly complete. However, the lack of behavioral details (e.g., error cases, response format) and no output schema means some context is missing, preventing a perfect score.

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

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

The input schema has 100% description coverage, with the 'domain' parameter fully documented in the schema. The description does not add any additional meaning or context beyond what the schema provides, such as format examples or validation rules, so it meets the baseline for high schema coverage without compensating further.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the tool's purpose with a specific verb ('Check') and resource ('domain availability'), and it distinguishes this tool from siblings by explicitly naming its function. The title 'domain_check' aligns perfectly with the described functionality, avoiding tautology.

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

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

The description provides explicit usage guidelines with a 'Best for' section listing specific scenarios (validating availability, pre-deployment checks, domain planning) and mentions 'Next steps: domain_create' and 'Related: domain_list', clearly indicating when to use this tool versus alternatives in the sibling set.

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