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

Annotations already declare readOnlyHint=true and openWorldHint=true, so safety is covered. The description adds useful context the annotations don't: it is limited to 'public' articles and returns 'metadata and body paragraphs,' clarifying content scope. It stops short of noting pagination or truncated bodies, so not a full 5.

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?

Three short sentences, front-loaded with the core action, then two routing hints. No filler; every sentence earns its place.

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?

An output schema exists so return values needn't be described, annotations cover the read-only/open-world profile, and the single required parameter is fully documented. Nothing an agent needs to invoke it correctly is missing.

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 100% with the url parameter described as 'Canonical IndieWire article URL' and zero enums. The description adds no syntax or format detail beyond the schema, so the baseline 3 is appropriate when the schema fully documents the single parameter.

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?

States a specific verb ('Fetch') and precise resource ('one public IndieWire article's metadata and body paragraphs'), including the scope of content returned. It also names the sibling tools it is not, so an agent can distinguish it from indiewire_headlines and indiewire_news without opening any schema.

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?

Explicitly routes the agent: 'Use indiewire_headlines to discover story cards' and 'Use indiewire_news for the general news feed.' This tells the agent both when this tool applies (have an article URL) and which alternatives to use for discovery, leaving nothing to inference.

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