fetch_page

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

With no annotations provided, the description carries the full burden. It discloses output capping ('max_chars'), no API key requirement, and content processing (strips navigation/ads). However, it does not mention rate limits or error handling, which are acceptable omissions for a simple fetch tool.

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 three sentences long, front-loaded with the main action and output. Every sentence adds value: purpose, usage, and behavioral details. No unnecessary words.

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?

Given the tool's simplicity and the presence of an output schema (so return values are covered), the description adequately covers what the tool does, how it processes content, and its limitations (max_chars). It also mentions authentication (no API key), which is useful context.

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?

The input schema has 0% description coverage, so the description must compensate. It explains the max_chars parameter ('Output is capped to max_chars characters') and gives a default. The url parameter is implied by the tool's purpose but not explicitly described, which is acceptable given its obvious nature.

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 action ('Fetch'), resource ('web page'), and output format ('clean, readable Markdown'). It also mentions stripping navigation/ads and extracting main article text, distinguishing it from siblings like web_search which returns search results.

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 gives a clear when-to-use scenario: 'Use this to read the full content of a URL (e.g. a search result).' It does not explicitly mention when not to use or compare with siblings, but the use case is well-defined and appropriate for this tool.

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