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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint, and non-destructiveness, so the safety profile is covered. The description adds valuable behavioral context beyond annotations: it discloses what gets stripped, what gets flagged, the free-tier limit of 10 calls/day, and the payment mechanisms via x402 or X-API-Key credits. It does not describe error behavior for malformed URLs, but the output schema likely covers return shape.

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 core purpose is front-loaded, and every sentence contributes useful information: transformation behavior, phishing checks, and billing mechanics. The billing details are dense but relevant to invocation; the trailing '[served by tools.moneytools.dev]' is minor overhead but not disruptive.

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 one-parameter tool with a full output schema, the description covers purpose, transformations, security checks, and payment requirements. It is largely complete; the only gap is explicit guidance on when to prefer this tool over related URL-parsing siblings.

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 the single 'url' parameter documented and given an example. The description does not add parameter-level meaning beyond what the schema already provides, so the baseline score of 3 is appropriate.

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 states a specific verb and resource: split a URL into parts and query params, strip tracking params, and flag phishing tricks. It gives concrete examples of tracking parameters (utm_*, fbclid, gclid) and phishing signals (user@host, raw IP, shorteners, punycode), making the tool clearly distinguishable from a plain URL metadata tool.

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?

Usage is implied by the described operations: use this to parse, clean, and security-check a URL. However, there is no explicit guidance on when to choose this over sibling tools like url_metadata or http_link_parse, and no stated exclusions or prerequisites.

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