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

The annotations already declare read-only, open-world, idempotent, and non-destructive behavior. The description adds meaningful context beyond annotations: it explains that it scans HTML link tags, does not subscribe to any feed, and returns discovered candidate feed URLs and titles.

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 front-loaded and efficient: it states the action, the safety guarantee, the return value, and the next step in a few clear sentences. The API documentation reference is somewhat extraneous but does not interfere with comprehension.

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 discovery tool with rich annotations, the description covers what the tool does, what it does not do, what it returns, and which tool to use next. No output schema exists, and the description adequately states the return value as a list of candidate feed URLs and titles.

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%, and the single url parameter is already documented as the website URL to scan for RSS/Atom feed links. The description reinforces that this is a website URL to inspect, but adds no syntax, format, or constraint details beyond the 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 states a specific verb and resource: inspecting a website URL and discovering RSS, Atom, and JSON feed links from HTML link tags. It clearly distinguishes this discovery operation from subscription or listing tools, especially by saying it does NOT subscribe and by naming subscribe_feed as the follow-up action.

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?

It gives clear usage context: this is for finding candidate feed URLs on a website, and subscribe_feed should be used afterward to subscribe. It does not explicitly contrast with sibling tools like list_feeds, but the purpose is sufficiently clear that an agent can infer when to use it.

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