Fetch MCP Server

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

No annotations are provided, so the description carries the full burden. It mentions the tool fetches a website and returns plain text, but lacks details on error handling (e.g., what happens if the URL is invalid), performance (e.g., timeouts or rate limits), or side effects (e.g., whether it makes network requests). This is a significant gap for a tool with no annotation coverage.

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 a single, clear sentence with no wasted words. It efficiently conveys the core functionality and output format, making it easy to understand at a glance.

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 complexity (a network fetch tool with no annotations and no output schema), the description is incomplete. It doesn't cover behavioral aspects like error conditions, response format details beyond 'plain text', or usage constraints, leaving gaps that could hinder an AI agent's ability to use the tool correctly.

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 100%, so the schema already documents both parameters (url and headers) fully. The description doesn't add any parameter-specific details beyond what the schema provides, such as examples or constraints, so it meets the baseline of 3 for high schema coverage.

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'), the resource ('a website'), and the specific output format ('plain text (no HTML)'). It distinguishes from sibling tools by specifying the output format, which differentiates it from fetch_html, fetch_json, and fetch_markdown.

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 usage by specifying the output format, suggesting it should be used when plain text is needed. However, it doesn't explicitly state when to use this tool versus the sibling tools (e.g., 'use fetch_txt when you need text without HTML tags, use fetch_html for raw HTML'), nor does it mention any prerequisites or exclusions.

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