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

Beyond the read-only and idempotent annotations, the description discloses the actual search strategy: alternate tags, Link header, feed-shaped links, common paths, legacy feeds, and the order of attempts. It also states that every tried rung is returned, giving agents useful expectations about output completeness.

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 dense but information-packed, with the tool purpose front-loaded and usage guidance at the end. No sentence is wasted, though the long semicolon-heavy sentence could be restructured for easier parsing.

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 no output schema, the description usefully explains the discovery algorithm, the cost-related option, and the situations in which the tool should be invoked. It could be slightly more explicit about the exact shape of the returned result, but nothing critical is missing.

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 schema already documents site, task_context, and all. The description adds no meaningful parameter-level semantics beyond the schema, making the baseline score of 3 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 opens with the specific verb 'Find' and a precise resource ('RSS/Atom/JSON feed(s) of a site'), then enumerates the discovery techniques used. It also distinguishes itself from the feed_items sibling by mentioning 'feed_items missed', making the tool's role clear.

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 tool explicitly states when to use it: when you need a feed URL, want all feeds from a site, or need to debug why feed_items missed something. It does not explicitly contrast with news_search, so it lacks a full when-not-to-use boundary, but the provided conditions are clear.

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