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 the tool is for 'Viewing TCP proxy configurations' and 'Auditing service endpoints,' which implies it's a read-only operation, but it doesn't explicitly state behavioral traits like whether it requires authentication, has rate limits, or what the output format looks like. The description adds some context but lacks detailed 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, starting with the core purpose in the first sentence, followed by bullet-point sections for usage guidelines. Every sentence earns its place by providing clear value, such as listing use cases and related tools, without unnecessary verbosity or repetition.

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 read operation with 2 parameters), no annotations, and no output schema, the description is mostly complete. It covers purpose, usage guidelines, and relationships well, but it lacks details on behavioral aspects like output format or error handling. This is a minor gap, so it scores slightly above the minimum viable level.

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 both parameters (environmentId and serviceId) fully documented in the input schema. The description doesn't add any parameter-specific details beyond what's in the schema, such as explaining how to obtain these IDs or their formats. With high schema coverage, the baseline score of 3 is appropriate as the schema does the heavy lifting.

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 verb ('List') and resource ('all TCP proxies for a service in a specific environment'), making the purpose specific and unambiguous. It distinguishes this tool from its siblings like tcp_proxy_create and tcp_proxy_delete by focusing on listing rather than creating or deleting proxies.

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 guidance with sections like 'Best for' (listing use cases), 'Prerequisites' (service_list), 'Next steps' (tcp_proxy_create), and 'Related' (domain_list, service_info). This clearly indicates when to use this tool and how it relates to alternatives, such as directing users to tcp_proxy_create for creation tasks.

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