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

Annotations already declare readOnly/idempotent/non-destructive, so the description's added value is the preservation rule (unrelated query parameters and page anchor survive) and determinism, which tell an agent what the output link will look like. It still leaves 'evidence-bounded result' undefined, but the key behavioral contract is disclosed.

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 compact sentences with the core action front-loaded and no filler. 'Evidence-bounded result' is unexplained jargon that costs a little clarity, but nothing is padded.

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?

An output schema exists, so return values need not be described, and the read-only compute semantics are clear from annotations. However, with zero parameter documentation and no alternative-tool routing, an agent is left to guess at the four required UTM fields' meaning.

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% across five parameters, yet the description names none of them individually (websiteUrl, source, medium, campaign, content) and gives no format or constraint guidance such as UTM value sanitization or content-vs-campaign roles. Only the general concept of a UTM link from a website URL is inferable.

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?

States a specific verb and resource ('Create one deterministic UTM link') plus the defining behavior of preserving unrelated query parameters and the anchor. An agent can distinguish it from the sibling toolfound_campaign_url_cleaner by the builder-vs-cleaner framing, though the sibling is never named.

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 never says when to reach for this tool versus the near-identical toolfound_campaign_url_cleaner or toolfound_inspect_public_link, and gives no prerequisites or exclusions. Usage is only implied by the verb 'Create'.

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