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

Beyond the readOnlyHint/idempotentHint annotations, the description discloses fan-out to multiple sources, the GDELT→GNews fallback chain, USPTO soft-fail due to PatentsView API sunset, and the return structure (changes[] grouped by source, total_changes count, pipeworx:// citation URIs). No contradictions with 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 dense but well-structured, front-loaded with query examples. Every sentence adds value—sources, fallback, parameter formats, output summary, and alternative are all covered. It is longer than ideal but justified by the tool's complexity.

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?

The tool is complex (multiple sources, fallback, soft-fail, parameter formats, output shape), and the description covers all essential aspects without an output schema. It states what the output contains, how to specify the time window, and when to choose a sibling tool, making it complete for correct invocation.

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%, so baseline is 3, but the description adds meaningful detail: `since` accepts ISO dates or relative shorthand with examples ('7d', '30d', '3m', '1y'), and `value` can be a ticker or zero-padded CIK. This exceeds schema descriptions and helps agents format parameters correctly.

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 in the last N days/weeks/months in ONE parallel call,' enumerating specific sources (SEC EDGAR, GDELT/GNews, USPTO). It also distinguishes itself from the sibling entity_profile by contrasting dynamic changes with 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?

Explicitly gives trigger query examples ('What's new with X', 'latest on Y', etc.) and names an alternative: 'Use entity_profile instead when you want the static profile ... regardless of window.' It also explains source fallback behavior, which helps set expectations for when GNews is used instead of GDELT.

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