fetch

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

With no annotations, the description carries full burden. It mentions handling multiple file types and returning markdown, but omits details on caching, redirect handling, or rate limits. The schema adds some behavior (POST bypasses cache), but the description does not summarize this.

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 sentences, each adding critical information: core function, supported formats, and usage guidance against alternatives. No waste or redundancy.

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 tool with 7 parameters and no output schema, the description covers core behavior, supported formats, and use cases. Missing details like error handling or timeouts, but schema covers parameter constraints.

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 100%, so the baseline is 3. The description adds no parameter-specific meaning beyond what the schema already provides. The mention of 'handles HTML...' is about output, not parameters, and does not enhance 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 fetches any URL and returns markdown content. It differentiates from sibling tools by noting 'no domain restrictions' and explicitly contrasts with the search tool for URL discovery.

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 explicit guidance to use this tool for reading web pages and directs users to the search tool for URL discovery. Does not contrast with other fetch-like siblings (e.g., get_alibaba_product), but the 'no domain restrictions' implies preference for generic use.

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