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

Annotations already declare readOnlyHint, openWorldHint, idempotentHint, and destructiveHint=false. The description goes further by detailing the fan-out behavior across SEC EDGAR, GDELT→GNews fallback, and USPTO with soft-fail condition, adding valuable behavioral context beyond annotations.

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 paragraph, but every sentence adds value. It is front-loaded with examples. Slightly more structure (e.g., bullet points for parameters) could improve scannability, but overall it is concise and informative.

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?

Given the complexity of the tool (multi-source fan-out, fallback logic, soft-fail), the description covers return format (structured changes grouped by source, total_changes count, citation URIs), error handling (GDELT→GNews fallback, USPTO soft-fail), and parameter caveats. No output schema exists, but the description sufficiently compensates.

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 already covers all three parameters with descriptions (100% coverage). Description adds extra meaning: explains 'since' accepts ISO date or relative shorthand, 'value' accepts ticker or CIK, and 'type' is limited to 'company'. This adds practical usage context.

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?

Description opens with concrete example queries ('What's new with X', 'latest on Y'), clearly stating it's a change feed for a company in the last N days/weeks/months. It explicitly distinguishes from sibling entity_profile, which provides 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 usage guidance: use this tool for change feeds in a time window, and use entity_profile instead for static profiles. Also includes example queries and parameter hints like 'Use "30d" or "1m" for typical monitoring.'

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