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

Beyond the readOnlyHint and openWorldHint annotations, the description discloses two important behavioral traits: the feed updates every 15 minutes and, critically, that the GDELT TV archive stopped updating around October 2024, so results are archived rather than live. This is substantial context an agent needs to interpret results correctly.

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 well structured: purpose first, then the no-query clarification, then update cadence, then the important archival caveat. Every sentence provides necessary information without padding.

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 zero-parameter tool with an output schema and readOnly/openWorld annotations, the description provides all essential context: what it returns, the no-query workflow, the update cadence, and the data freshness caveat. Nothing critical is missing for an agent to select and invoke it 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?

The tool has zero parameters, and the schema covers 100% of that, so the baseline is 4. The description adds the relevant clarification that no query is required, which reinforces the no-parameter nature of the call.

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 uses a specific verb ('Retrieve') and names the exact resource: trending topics, keywords, and phrases currently dominating US television news. It also clarifies there is no query required, which differentiates it clearly from the sibling search tools like gdelt_search_tv.

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 clearly states when to use the tool: when you want current trending memes with no query. The explicit 'No query required' communicates the main use case, though it does not explicitly name alternatives or say when not to use it.

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