MCP Proxy Server

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 mentions that the tool grants internet access and can fetch up-to-date information, which is useful context. However, it doesn't disclose critical behavioral traits like rate limits, authentication needs, error handling, or what happens with invalid URLs. The description adds some value but leaves significant gaps for a tool that performs network operations.

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 two paragraphs: the first is concise and front-loaded with the core functionality, but the second paragraph contains redundant information about internet access that could be condensed. While not overly verbose, the second sentence in the first paragraph and the entire second paragraph don't earn their place efficiently, reducing overall conciseness.

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 no annotations, no output schema, and a tool that performs network operations with 4 parameters, the description is moderately complete. It covers the basic purpose and context of internet access but lacks details on return values, error conditions, and operational constraints. For a fetch tool, more behavioral context would be expected to achieve higher completeness.

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 all four parameters thoroughly. The description mentions optional markdown extraction, which relates to the 'raw' parameter (when false), but doesn't add meaningful semantic details beyond what the schema provides. This 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 tool's purpose: fetching a URL from the internet and optionally extracting contents as markdown. It specifies the verb ('fetches') and resource ('URL'), though it doesn't differentiate from siblings since there are none. The second paragraph adds context about internet access but doesn't enhance the core purpose statement.

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 context by mentioning that the tool now grants internet access for fetching up-to-date information, which suggests it should be used when current data is needed. However, it lacks explicit guidance on when to use this tool versus alternatives (though no siblings exist) or any exclusions. The guidance is somewhat implied rather than clearly stated.

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