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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false. The description adds valuable behavioral context beyond annotations: it uses a HEAD probe (no page download), provides timing waterfall, identifies the exact failure phase, and mentions the payment mechanism. No contradictions with 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 detailed but well-structured, front-loading the main functionality in the first sentence. It is not overly verbose, though the cost note could be more prominent. Overall efficient use of space.

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 output schema exists (as noted in context signals), the description covers the tool's comprehensive output thoroughly, listing many components. It is complete for a health monitoring tool's purpose, and the presence of an output schema offloads detailed return structure.

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 coverage is 100% with a single parameter 'url' having a clear description. The description does not add further input semantics; it focuses on output. Baseline of 3 is appropriate as schema already documents the parameter adequately.

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 explicitly states it produces a 'deep uptime & health report' from a single HEAD probe, listing numerous specific metrics (DNS, TCP, TLS, TTFB, certificate, etc.). It distinguishes itself from siblings like get_dns or get_ping by being a comprehensive, one-call tool that covers multiple layers.

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 for detailed health monitoring and notes cost ($0.01 per call). However, it does not explicitly state when to use this tool versus simpler sibling tools (e.g., get_uptime, get_dns) or exclude scenarios where a full page load is required. Guidance on alternatives is absent.

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