fetch

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

With no annotations, the description carries the full burden of behavioral disclosure. It explicitly reveals the SSRF-safety, the return payload (status, contentType, markdown|text), the size limit (200KB), and the intended scope (analytics-only). This is substantial and goes beyond a generic fetch description.

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, dense sentence that front-loads the core action and packs in all key behavioral constraints without fluff. Every clause earns its place: action, safety, return type, size cap, usage scope.

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 simple two-parameter fetch tool with no output schema and no annotations, the description covers the essential return information (status, contentType, content format) and constraints (SSRF-safe, 200KB cap, analytics-only). It lacks explicit details on error handling or redirects, but these are minor for this tool's simplicity.

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% (both url and format have descriptions). The description adds no new parameter-specific detail beyond what the schema already states (public URL, output format enum). It reinforces 'public' and the markdown|text options, but this is redundant with the schema, so baseline 3 applies.

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 a public URL' and adds differentiating specifics: SSRF-safe, returns status/contentType/markdown|text, 200KB cap, and analytics-only use. This distinguishes it from siblings like whois, dns, or normalize-url without needing to name them.

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?

No explicit guidance on when to use this tool versus alternatives is provided. It doesn't mention sibling tools or conditions that would route an agent to fetch instead of paste_read, whois, etc. The 'Analytics-only' note is a restriction, not usage direction. There is no 'use when' or 'not for' guidance.

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