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 mentions that the tool lists 'all domains (both service and custom)' and hints at its read-only nature through usage contexts like 'Viewing' and 'Auditing,' but it does not explicitly state whether it's a safe read operation, requires specific permissions, or details output format. It adds some value but lacks comprehensive behavioral disclosure.

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, prerequisites, next steps, and related tools. Every sentence earns its place by providing clear, actionable information without redundancy or fluff.

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 complexity (a list operation with 3 parameters), no annotations, and no output schema, the description does a good job by covering purpose, usage, and context. However, it lacks details on output format (e.g., what data is returned) and behavioral aspects like pagination or error handling, which would be needed for full completeness.

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?

Schema description coverage is 100%, so the schema already documents all three parameters (projectId, environmentId, serviceId) with descriptions. The description does not add any parameter-specific details beyond what the schema provides, such as format examples or dependencies, so it meets the baseline for high schema coverage.

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: 'List all domains (both service and custom) for a service.' It specifies the verb ('List'), resource ('domains'), and scope ('for a service'), and distinguishes it from siblings like domain_check, domain_create, domain_update, and domain_delete by focusing on listing rather than other operations.

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 guidance on when to use this tool: 'Best for: Viewing service endpoints, Managing domain configurations, Auditing domain settings.' It also lists prerequisites ('service_list'), next steps ('domain_create, domain_update'), and related tools ('service_info, tcp_proxy_list'), clearly indicating context and alternatives.

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