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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false. The description adds useful behavioral context beyond this: Data Parrot AI analysis is included only for open deals, and the response includes seller-entered next steps and future scheduled activities. No contradiction 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?

Two sentences, front-loaded with the core action and then enriched with return contents and use cases. Every clause adds value, and there is no repetition of schema or annotation information.

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 an output schema present, the description does not need to spell out return values. It covers the main use cases, a conditional behavioral detail, and gives a hint about the columns parameter. Slightly more explicit guidance on how columns map to the parameter would make it fully complete.

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 0%, so the description must compensate. It does add partial meaning: deal_id is 'one known deal ID' and columns are implied by 'selectable HubSpot fields.' However, it does not explain how columns should be provided, the meaning of null, or the default behavior, leaving an important gap for a schema with no property 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 opens with a specific verb and resource: 'Return details for one known deal ID,' which clearly distinguishes this from the plural get_deals sibling. It also lists concrete content areas (fields, custom properties, associations, next step, activities, AI analysis), making the tool's purpose unambiguous.

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 clear usage context: use it for deal details, forecast confidence, or a deal's recorded won/lost reason. It does not explicitly name alternative tools or state when not to use them, but the 'one known deal ID' phrasing and use cases imply the boundary against get_deals and get_forecast.

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