mcp-southwest

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It adds useful context about the timing constraint ('Check-in opens exactly 24 hours before departure') and the return values ('Returns boarding group (A/B/C) and position number'), but it doesn't cover other behavioral aspects like error conditions, authentication needs, or rate limits. This is adequate but has gaps for a tool with no annotations.

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 front-loaded with the core purpose, followed by timing and return details in just two sentences. Every sentence earns its place by providing essential information without redundancy, making it highly efficient and well-structured.

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 moderate complexity (3 required parameters, no output schema, no annotations), the description is fairly complete. It covers purpose, timing, and return values, which are crucial for usage. However, it lacks details on error handling or prerequisites, leaving some gaps in contextual understanding.

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 thoroughly. The description doesn't add any additional meaning or context about the parameters beyond what's in the schema. According to the rules, with high schema coverage, the baseline score is 3 even without parameter info in the description.

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 ('Check in online for a Southwest flight'), identifies the resource ('a Southwest flight'), and distinguishes it from siblings like 'get_boarding_pass' or 'get_reservation' by focusing on the check-in process. It provides a complete, unambiguous purpose statement.

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 clear context for when to use this tool ('Check-in opens exactly 24 hours before departure'), which helps time its invocation appropriately. However, it doesn't explicitly state when NOT to use it or mention alternatives among the siblings, such as how it differs from 'get_boarding_pass' or 'get_reservation'.

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