web_fetch

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

With no annotations provided, the description carries the burden of behavioral disclosure. It mentions using Mozilla Readability, but does not disclose whether JavaScript executes, rate limits, authentication needs, error handling, or what happens with non-HTML content.

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?

Single sentence that is front-loaded with the core action. No redundant words. Every part contributes meaning.

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 simple but lacks an output schema or description of the return format (e.g., plain text, markdown). Given no output schema, the description should mention the output structure. It is adequate but incomplete for an agent to fully understand the behavior.

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 baseline is 3. The description adds no extra meaning beyond the schema: the URL parameter's description is already present, and max_chars has default/range in the schema. No additional context on why to adjust max_chars or what the extraction output looks like.

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 verb 'Fetch and extract', the resource 'readable content from a web page URL', and the method 'using Mozilla Readability'. It effectively distinguishes from the sibling 'web_search' which is for searching, not fetching specific pages.

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 implies the tool is for extracting content from a single URL, but lacks explicit guidance on when to use it versus alternatives. No mention of when not to use, prerequisites, or comparisons to 'web_search'.

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