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

Beyond the readOnly/idempotent annotations, the description discloses fan-out behavior, GDELT→GNews fallback conditions, USPTO soft-fail due to API sunset, accepted date formats, and the return structure (changes[], total_changes, citation URIs). This is rich, non-obvious behavioral context.

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 longer than necessary but every sentence carries useful information. It opens with query examples (slightly delayed purpose statement) but remains well-structured and free of fluff. Slightly verbose yet highly 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 no output schema, the description fully describes return shape (changes[] grouped by source, total_changes, pipeworx:// URIs), source fallbacks, and parameter nuances. It also references the PatentsView sunset, making the tool's current limitations explicit.

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%, but the description adds value by explaining the 'since' relative shorthand with examples ('7d', '30d', '3m', '1y') and recommends '30d' or '1m' for typical monitoring. It also clarifies the output grouping by source, which maps to parameter usage.

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' and explicitly contrasts with entity_profile. It lists specific sources (SEC EDGAR, GDELT/GNews, USPTO) and gives query examples, leaving no ambiguity about purpose.

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 provides explicit query phrasings ('What's new with X', 'latest on Y') and an explicit alternative: 'Use entity_profile instead when you want the static profile...'. This tells the agent exactly when to use this tool versus a sibling.

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