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 discloses that the tool is for authentication configuration and is 'only needed if not set in environment variables', adding useful context about prerequisites. However, it lacks details on behavioral traits like error handling, rate limits, or what happens on success/failure, leaving gaps for a mutation tool.

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, using bullet points and symbols (✓, ×, →) to organize information efficiently. Every sentence earns its place by providing purpose, usage guidelines, and next steps without unnecessary fluff, 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 complexity (a single-parameter mutation tool with no annotations or output schema), the description is mostly complete. It covers purpose, usage, and exclusions well. However, it lacks details on behavioral outcomes (e.g., what happens after configuration, error cases), which would be beneficial for full completeness in the absence of annotations.

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%, with the schema fully documenting the 'token' parameter. The description does not add any parameter-specific information beyond what the schema provides, such as format details or examples. Baseline 3 is appropriate since the schema handles the heavy lifting, but no extra value is added.

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: 'Configure the Railway API token for authentication' with the specific verb 'configure' and resource 'Railway API token'. It distinguishes from siblings by explicitly stating what it's not for (e.g., project configuration, service settings), making it distinct from tools like project_create or service_list.

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: 'Best for: Initial setup, Token updates, Authentication configuration' and 'Not for: Project configuration, Service settings, Environment variables'. It also suggests 'Next steps: project_list, service_list' and 'Related: project_create', offering clear alternatives and context for when to use this tool versus others.

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