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

Annotations already indicate readOnly, openWorld, idempotent, and non-destructive. The description adds significant operational detail: parallel fan-out to multiple sources, GDELT→GNews fallback, USPTO soft-fail due to API sunset, and return structure. This goes well beyond annotations and sets correct expectations.

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?

Dense but efficient: starts with query examples, then states the core function, lists sources, and closes with an alternative. No fluff; every sentence adds essential information.

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 tool with no output schema, the description fully covers the return shape (changes[] grouped by source, total_changes, citation URIs), the supported time windows, the fallback behavior, and the limitation (patents soft-fail). This is a complete operational picture for a complex aggregation tool.

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 covers all three parameters at 100%, so baseline is 3. The description adds value by explaining `since` formats ('ISO date' or 'relative shorthand') with examples and recommending '30d' or '1m' for typical monitoring. This extra guidance justifies a 4.

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?

Clear verb ('change feed') and resource ('company'), with concrete example queries that illustrate the intent. Explicitly distinguishes itself from entity_profile, which covers static profiles.

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?

Provides explicit 'when to use' via example natural-language queries, and an explicit alternative ('Use entity_profile instead when you want the static profile...'). Also explains fallback behavior and window syntax, giving clear context for selection.

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