Railway MCP Server

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

No annotations are provided, so the description carries full burden. It describes the tool's function (list deployments) and scope (recent, for a service in an environment), but doesn't disclose important behavioral traits like pagination behavior (though limit parameter is documented in schema), rate limits, authentication requirements, or error conditions. The description adds some context but leaves gaps for a read operation.

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). Every sentence earns its place - the bullet points efficiently convey usage context without redundancy. The information is front-loaded with the core purpose stated first.

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 4 parameters (3 required) and 100% schema coverage but no output schema, the description provides good contextual completeness. It covers purpose, usage scenarios, prerequisites, and relationships to other tools. The main gap is lack of output format information (no output schema exists), but otherwise it's quite complete for this tool type.

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 parameters. The description adds value by mentioning 'recent deployments' (which relates to the limit parameter's default of 10) and noting that environmentId is 'usually obtained from service_list'. This provides useful context beyond the schema's technical descriptions.

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 with specific verb ('List') and resource ('recent deployments for a service in a specific environment'). It distinguishes from sibling tools like deployment_logs (which shows logs) and deployment_trigger (which initiates deployments). The title is null, so the description fully defines the tool's function.

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 'Best for' section (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 for 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.