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

No annotations are provided, so the description carries the full burden. It does disclose two real behavioral traits beyond the schema: the shape of the returned entries and a per-call cost of 1 credit. It omits error behavior, pagination/entry-count limits, and any auth or rate-limit context.

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 tight sentences with zero filler: purpose and return shape first, cost last. Every clause earns its place.

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 2-parameter, no-annotation, no-output-schema tool, the description adequately covers purpose, return fields, and cost. It falls short on the limit parameter and on failure/empty-feed behavior, which an agent would need when a feed returns nothing or a URL is not a valid feed.

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 coverage is only 50%: url is documented in the schema, but limit (default 50, max 200) has no description anywhere. The description never mentions how many entries are returned or how limit affects the result, leaving the second parameter's semantics entirely to the agent's inference.

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?

Specific verb (fetch/parse) plus specific resource (RSS/Atom feed) and an enumeration of the returned fields (title, link, date, summary). An agent immediately knows what it gets back. However, it never distinguishes itself from feed-adjacent siblings like crawl_site, scrape_page, extract_content, or fetch_json.

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 states no when-to-use or when-not-to-use conditions and names no alternative. It implies the input must be a feed URL, but does not tell the agent to prefer parse_feed over scrape_page/extract_content when the target is a syndication feed, nor what happens with a non-feed page.

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