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

With no annotations provided, the description carries the behavioral disclosure burden. It discloses the paid cost ($0.001 USDC), normalization of text, the requirement for a public HTTPS page, and the conditional return of a compact diff when a prior snapshot exists. It does not detail failure modes or what happens when no snapshot is available, but it provides substantial useful behavior context.

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 sentence with no filler. It front-loads the paid nature and the core purpose, then immediately provides the mechanism and output condition. Every phrase earns its place.

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 simple two-parameter tool, the description covers the essential context: cost, input constraints, processing behavior, and expected output. It leaves minor gaps such as exact behavior when no prior snapshot exists, but nothing critical prevents an agent from invoking the tool correctly.

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 0%, so the description must compensate. It does: 'url' is clarified as a public HTTPS page with normalized text, and 'previous_hash' is clarified as a SHA-256 hash. This adds meaning well beyond the bare schema properties.

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 a specific action: checks normalized text on a public HTTPS page against a previous SHA-256 hash. It also distinguishes itself from sibling tools like check_url and check_package by focusing on change detection rather than generic URL or package validation.

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 makes the intended use case clear: use this tool when you have a URL and a prior SHA-256 hash and want to detect changes. It does not explicitly name alternatives or exclusions, but the conditions are specific enough to guide selection.

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