Scrape a page

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

Annotations already declare readOnly, non-destructive, open-world behavior, so the description is not obligated to restate safety. It adds genuinely new context: robots.txt is respected and blocked pages surface as errors rather than content, which prevents an agent from misreading an empty result as a successful scrape. It does not cover caching behavior or rate/latency characteristics.

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 tight sentences: capability first, sibling routing second, a behavioral caveat last. No filler, and the most important information is front-loaded.

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 complex, 27-parameter tool with no output schema, the description covers purpose, alternatives, default output, and the robots.txt failure mode, which is enough to call it correctly in the common case. Gaps remain around caching/conditional-request semantics and browser actions, but they are secondary for the typical single-page scrape.

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?

With 27 parameters and only ~48% schema description coverage, the description needs to compensate and largely does not. It only clarifies the formats parameter (markdown is the default, plus html/rawHtml/links/images/metadata); high-impact options like proxy restrictions, engine, actions, redactPII, lockdown, zeroDataRetention, storeInCache, and conditional-request fields are left to the schema or undocumented entirely.

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?

States a specific verb and resource (fetch one URL, return clean content) and enumerates the default and alternative output formats. It also names each sibling it is not, so an agent can distinguish single-page scraping from batch, map, and crawl without opening any schema.

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?

Gives an explicit selection rule: use this when you already know the page, use pagesift_batch_scrape for several known URLs, pagesift_map to discover URLs, pagesift_crawl to collect a whole site. Every alternative is named with the condition that selects it.

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