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 states it's a lookup/read operation and specifies the return data, but lacks details on error handling (e.g., invalid inputs), authentication needs, rate limits, or whether it's idempotent. For a tool with no annotations, this leaves significant gaps in understanding its operational behavior.

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 a single, efficient sentence that front-loads the purpose and key details (parameters and returns) without unnecessary words. Every part of the sentence contributes directly to understanding the tool's function, making it highly concise 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 adequate but incomplete. It covers the basic purpose and return data but lacks behavioral context (e.g., error cases) and doesn't fully compensate for the absence of annotations or output schema, leaving the agent with some uncertainty about execution.

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 clear descriptions for each parameter (e.g., '6-character booking confirmation number'). The description adds minimal value beyond the schema by mentioning the parameters in context but doesn't provide additional semantics like format examples or constraints. Baseline 3 is appropriate since the schema already documents parameters well.

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 ('Look up an existing Southwest reservation'), the required identifiers ('by confirmation number and passenger name'), and the return data ('flight details, fare type, and booking status'). It distinguishes from siblings like 'get_flight_details' or 'search_flights' by focusing on retrieving a specific reservation rather than general flight information or search capabilities.

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 implies usage when you have a confirmation number and passenger name to retrieve reservation details, but it doesn't explicitly state when to use this tool versus alternatives like 'get_flight_details' (which might not require passenger info) or 'search_flights' (for broader queries). No exclusions or prerequisites are mentioned, leaving some ambiguity for the agent.

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