Parse an RSS feed, Atom feed, or XML sitemap

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

With no annotations, the description carries the burden of behavioral disclosure. It reveals auto-detection behavior, return type, and cost implications. However, it omits details on error handling, redirects, payload size limits, or what 'behind a wall' means, leaving gaps for a tool that performs network fetches.

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?

Three dense sentences deliver high value without fluff. Each sentence provides essential information: input formats, auto-detection, output structure, and cost model. Excellent front-loading of the core purpose.

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 parse tool with only 2 parameters and no output schema, the description covers the main behaviors, including format handling, output shape, and cost nuance. The only notable gap is the undocumented free_only parameter and edge-case behaviors, but overall it is sufficiently complete for an agent to select and invoke the tool correctly.

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% — free_only lacks a schema description. The description does not explain free_only's meaning beyond implying a free-fetch default, and it does not discuss parameter syntax or interplay. This is insufficient to compensate for the schema's missing coverage on free_only.

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?

Description clearly states 'Fetch and parse an RSS 2.0 feed, Atom 1.0 feed, or XML sitemap', naming specific formats and output type. This distinguishes parse_feed from sibling scraping tools, which target specific websites or general web scraping.

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?

Provides clear context for when to use the tool (for feeds/sitemaps) and highlights a key differentiator: 'Free direct fetch — no Bright Data credit unless the feed is behind a wall.' However, it does not explicitly name alternative tools or state when NOT to use it, so it doesn't reach a 5.

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