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

Annotations already declare read-only, idempotent, open-world, and non-destructive; the description goes further with concrete behavior: parallel fan-out, GDELT→GNews fallback on rate limits/5xx, USPTO soft-fail after sunset, and structured grouped output with citation URIs. This exceeds annotation coverage.

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 dense but every clause earns its place: user intents, source fan-out, fallback logic, parameter formats, return shape, and the alternative tool. No filler or redundant restatement of the title.

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 multi-source, fallback-rich tool with no output schema, the description fully covers inputs, source behavior, output shape (changes[] grouped by source, total_changes, citations), and the alternative static-profile path. There are no critical gaps.

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 description coverage is 100% and already includes examples for `since` (ISO or relative) and `value` (ticker or CIK). The description repeats the `since` formats but adds no new parameter-level meaning beyond the schema, so baseline 3 applies.

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 clearly states the tool provides a change feed for a company over a time window, naming specific source types (SEC EDGAR, GDELT/GNews, USPTO). It differentiates itself from the sibling entity_profile by explicitly telling when to use that instead.

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?

It gives example user queries, provides typical values for the `since` parameter, and explicitly contrasts with entity_profile ('Use entity_profile instead when you want the static profile'). This is strong when-to-use and alternative guidance.

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