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

With no annotations, the description must carry behavioral disclosure, and it does add one useful privacy-related trait: 'Page content is not stored.' It also implies a read-only status check by saying 'Return.' However, it does not disclose error behavior, side effects, or whether input parameters are actually discarded; the schema's 'discarded' notes are not repeated in the description.

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 short, front-loaded with the primary behavior, and contains no filler. The second sentence earns its place as a privacy note, but the overall terseness feels thin relative to the nine-parameter schema, so it stops short of a 5.

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 nine optional parameters, no output schema, no annotations, and a crowded sibling list containing several URL-focused tools, this description is not complete enough. It does not specify the return format beyond three fields, which parameters to use, how to handle the optional extras, or how this differs from fetch-status and normalize-url.

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%, so the baseline is 3, and the description adds little beyond mentioning a URL. It does not explain how the other eight optional parameters relate to the tool, why they all exist, or which one should be supplied; the agent is left with a confusing schema.

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 tool returns host, scheme, and HTTP status for a URL, so the core action and resource are identifiable. However, the name 'citation' is not explained, and siblings like fetch-status, browser-url-ok, and normalize-url suggest overlapping URL-related purposes, so the description does not differentiate this tool from those.

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?

There is no guidance on when to use this tool versus the many URL-related siblings, nor any mention of when not to use it. The description only states what it returns, leaving the agent to guess whether this is the right tool for fetching status, checking URL shape, or something else.

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