fetch

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It transparently lists the return fields (url, final_url, content_type, text, byte_count) and mentions an error field with a stable string code. However, it does not discuss cleaning behavior, redirects, timeouts, size limits, or other operational details that could affect usage.

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 concise and well-structured: a single sentence stating the core behavior, followed by an Args block and Returns block. Every sentence provides necessary information without fluff, and the most important information (what the tool does) 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?

The tool is relatively simple, and the description provides a clear functional overview and return contract. However, it lacks usage guidance relative to sibling tools and does not define the 'stable string code' values or content type semantics. Given the low annotation coverage and the existence of sibling tools, the description is adequate but incomplete for fully-informed invocation.

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 0%, so the description must compensate. It does explain the 'url' parameter as requiring an http:// or https:// URL, which adds meaning beyond the schema. However, the 'ctx' parameter is not described at all, leaving a gap in parameter understanding.

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 clearly states the tool's function: 'Fetch a URL and return its cleaned main text content.' This is a specific verb+resource combination that distinguishes it from siblings like search, scrape_blog, and deep_scrape by emphasizing the 'cleaned main text' output.

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?

There is no explicit guidance on when to use this tool versus alternatives. The description does not mention any exclusions, prerequisites, or comparisons to sibling tools. It only provides the purpose and return format, leaving usage context entirely to the agent.

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