Pagebolt

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

With no annotations provided, the description carries full burden. It effectively discloses that this is a read-only listing operation (implied by 'List all available'), though it doesn't mention potential limitations like rate limits, authentication requirements, or whether the list is static/dynamic. The description adds practical context about how the output is used with another tool.

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?

Two tightly focused sentences with zero waste. The first sentence states the purpose with helpful examples, the second provides crucial usage guidance. Every word earns its place, and the structure is front-loaded with the core functionality.

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 parameterless read-only tool with no output schema, the description provides excellent context about what the tool does and how to use its output. It could slightly improve by mentioning the return format (e.g., array of strings) or any limitations, but given the simplicity of the tool, it's nearly complete.

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?

The tool has 0 parameters with 100% schema description coverage. The description appropriately doesn't waste space discussing nonexistent parameters. It instead focuses on the tool's purpose and output usage, which is the correct emphasis for a parameterless tool.

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 verb ('List') and resource ('all available device presets for viewport emulation'), with concrete examples (iphone_14_pro, macbook_pro_14). It distinguishes from sibling tools by focusing on device preset enumeration rather than screenshot capture, PDF generation, or session management.

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 explicitly states when to use this tool ('Use the returned device names with the viewportDevice parameter in take_screenshot'), providing a clear alternative context. It directly links to a specific sibling tool (take_screenshot) and explains the relationship between tools.

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