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

Beyond the readOnlyHint and idempotentHint annotations, the description adds key behavioral context: it requires an agency API key, only ever returns the calling agency's own leads, and distinguishes this inbox from the pipeline board. It also clarifies that the leads are from portal, website, or microsite enquiries.

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 front-loaded with the core action and ordering, then adds tightly relevant usage guidance and mental-model context. Every sentence earns its place without fluff or redundancy.

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 that all parameters are optional and the annotations already declare read-only, idempotent, non-destructive behavior, the description fully covers what an agent needs: purpose, differentiation, scope, auth expectation, and examples. No important context appears missing.

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 schema already documents since and property_reference clearly, and limit is self-evident from its type, default, minimum, and maximum. The description does not add much parameter-level meaning beyond the schema, but the schema itself is strong enough that no critical gap remains.

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 uses a specific verb ('List') with a clear resource ('recent enquiries (leads) for YOUR agency's CRM') and specifies the ordering ('newest first'). It also differentiates from the sibling tool my_pipeline by explaining that leads being actively worked move to the pipeline board.

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 explicitly says when to use the tool, such as when the agent asks 'what came in today?', and when not to use it by directing pipeline-board leads to my_pipeline. It even addresses a common misinterpretation: an empty inbox for board-first agencies is not the same as having no leads.

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