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

Beyond annotations (readOnlyHint, idempotentHint, etc.), the description reveals that the tool fans out to three data sources (SEC, GDELT/GNews, USPTO) with fallback logic (GDELT preferred, GNews when rate-limited) and a soft-fail condition (USPTO). This adds valuable context about internal behavior not captured by 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 coherent paragraph that front-loads example queries, then explains data sources and fallbacks, parameter details, and ends with a sibling comparison. Each sentence adds value, but the density could be slightly improved with bullet points or clearer segmentation.

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 read tool with three parameters and no output schema, the description covers source behavior, fallback logic, soft-fail conditions, and parameter formats. It addresses temporal boundaries (window) and provides a comparison with a sibling. Minor gaps: no mention of return structure details (e.g., 'pipeworx:// citation URIs' is listed but not explained), but overall sufficient.

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%, but the description enhances parameter understanding by providing practical examples for 'since' (ISO date, relative shorthand like '30d', '1y') and clarifying that 'value' accepts either ticker or zero-padded CIK. This reduces ambiguity and adds usage guidance beyond the schema's formal descriptions.

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 starts with concrete example queries ('What's new with X', 'updates on Acme') and states it returns a change feed for a company over a window. It explicitly distinguishes from sibling tool entity_profile ('Use entity_profile instead when you want the static profile'). This provides a specific verb ('return changes') and resource ('company change feed'), with sibling differentiation.

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?

The description explains when to use this tool ('What's new with X' queries) and when to use the sibling entity_profile ('static profile'). It also notes a temporal concern (USPTO soft-fails after May 2025). However, it does not explicitly state when not to use it or mention alternatives for other query types.

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