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

Annotations already establish readOnlyHint=true and openWorldHint=true, so the safety profile is covered. The description usefully adds that the output is 'static' (a canned sample rather than live data), which is genuine behavioral context, but it omits whether it counts against quotas or is rate-limited.

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?

Two short sentences, front-loaded with the tool's nature and followed immediately by the one input instruction. No wasted words, though terseness is approaching under-specification rather than tight editing.

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?

With no output schema, the description should carry more about what the sample output contains or its format, since previewing output is the tool's whole point. It covers the input concept adequately for a 1-param tool but leaves the return shape entirely unspecified.

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 0% and the single required 'slug' param is an undocumented enum of 10 values. The phrase 'paid route slug' adds the key meaning that each enum value maps to a paid route, but the individual slugs (e.g. 'se-validate', 'url-markdown') carry no explanation beyond what sibling names hint at.

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 states the tool returns a 'static sample output' and takes a 'paid route slug', so the resource is identifiable but the verb is implicit and 'demo' gives no standalone signal. It loosely distinguishes itself as the free preview counterpart to the paid route tools, but an agent must infer that relationship rather than being told it.

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?

'Free static sample output. Pass a paid route slug' implies usage (call this to preview a route's output without paying), and the 'paid' qualifier hints at the sibling pricing tools. However, it never explicitly says when to prefer this over the real sibling tool or what happens after previewing, leaving usage to inference.

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