Railway MCP Server

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

With no annotations provided, the description carries the full burden. It states this is a list operation (implied read-only) and mentions it returns 'recent' deployments with a default limit of 10, which adds useful behavioral context. However, it doesn't disclose pagination behavior, error conditions, or authentication requirements, leaving some gaps for a tool with no annotation coverage.

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 with clear sections (API tag, purpose, best for, prerequisites, next steps, related tools) and uses bullet points/arrows for readability. Every sentence earns its place by providing distinct guidance without redundancy.

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?

For a read-only list tool with no annotations and no output schema, the description provides good contextual guidance (prerequisites, next steps, related tools) and clear purpose. However, it doesn't describe the return format or structure, which would be helpful given the lack of output schema. The completeness is strong but not perfect.

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 4 parameters thoroughly. The description doesn't add any parameter-specific details beyond what's in the schema (e.g., it doesn't explain format of IDs or how 'recent' relates to the limit parameter). Baseline 3 is appropriate when 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 specific action ('List recent deployments'), resource ('for a service in a specific environment'), and scope ('recent'). It distinguishes from sibling tools like deployment_logs (which gets logs for a specific deployment) and deployment_trigger (which initiates new deployments), making the purpose unambiguous.

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 with 'Best for' sections (viewing deployment history, monitoring service updates), prerequisites (service_list), next steps (deployment_logs, deployment_trigger), and related tools (service_info, service_restart). This gives clear context on when to use this tool versus alternatives.

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