SnapAPI MCP Server

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

With no annotations, description carries full burden. It discloses what each preset contains (viewport, device scale factor, mobile flag) and categorizes the devices (phones, tablets, desktops), but omits safety traits, rate limits, or caching behavior typical of read operations.

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?

Three sentences with zero waste: purpose statement, content explanation, and usage instruction. Information density is high with no 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 zero-parameter discovery tool without output schema, the description adequately explains the return concept (presets with IDs) and their relationship to consumer tools (screenshot, video). Covers necessary context for agent selection.

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?

Zero parameters present; baseline score applies per rubric. The description appropriately requires no additional parameter explanation given the empty input schema.

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?

Clear verb 'List' with specific resource 'device presets'. The scope is well-defined ('for screenshot and video emulation') and distinguishes from siblings like analyze or pdf by explicitly mentioning the screenshot/video domain.

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?

Explicitly states the output intent: 'Pass the device id to the screenshot or video tool.' This establishes the workflow (use before screenshot/video) and links to specific sibling tools, though it lacks explicit 'when not to use' guidance.

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