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. It states the tool checks domain availability, which implies a read-only operation without side effects, but it doesn't disclose behavioral traits like rate limits, authentication needs, error conditions, or what 'available for use' entails (e.g., registration status). The description adds basic context but lacks detailed behavioral information.

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 concise, with a clear purpose statement upfront, followed by bullet-point usage guidelines and related tool references. Every sentence earns its place by providing actionable information without redundancy, making it easy to scan and understand.

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 (one parameter, no output schema, no annotations), the description is reasonably complete. It covers purpose, usage guidelines, and related tools, but lacks details on behavioral aspects like response format or error handling. For a simple read operation, this is mostly adequate, though some gaps remain in transparency.

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 schema description coverage is 100%, with the single parameter 'domain' fully documented in the schema. The description doesn't add any parameter-specific semantics beyond what the schema provides (e.g., no format examples like 'example.com' or validation rules). Since schema coverage is high, the baseline score of 3 is appropriate.

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: 'Check if a domain is available for use.' It uses a specific verb ('Check') and resource ('domain'), and distinguishes it from sibling tools like domain_create, domain_list, domain_update, and domain_delete by focusing on availability validation rather than creation, listing, modification, or deletion.

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 domain availability, pre-deployment checks, domain planning) and includes 'Next steps: domain_create' and 'Related: domain_list' to guide when to use alternatives. This clearly indicates when this tool is appropriate versus other domain-related tools.

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