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

Annotations already declare readOnlyHint=true, and the description adds useful behavioral context: it explains the score's calculation (z-scored against trailing-year baseline), lists the components, and notes 'Updates: daily.' This goes beyond the annotations without contradicting them.

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 information-dense yet efficient, with a clear lead sentence about the score, a usage sentence, and an update-frequency sentence. It avoids redundancy and remains focused, though it could be slightly more concise given the list of field names.

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?

With no output schema, the description compensates by listing the returned fields and explaining the score's meaning. It also covers the optional history behavior via the schema, making the tool's overall behavior sufficiently clear for most use cases.

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?

The sole parameter 'days' is fully described in the schema with its range, purpose, and the Gold tier requirement (100% schema coverage). The tool description itself doesn't add additional parameter details, so it relies appropriately on the schema.

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 returns a 0-100 pharmacogenomic adoption-momentum score and explicitly lists the output fields (e.g., pgx_adoption_score, z_pair_change_events). It also includes specific use-case triggers ('Call when...'), making it easy to distinguish from sibling tools in the ADW family.

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 provides explicit usage guidance with 'Call when the user asks about PGx guideline expansion...' and related scenarios. It clearly states when to invoke the tool, but it doesn't mention when not to use it or name alternative sibling tools, so it's not a full 5.

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