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

Annotations already cover the safety profile (readOnly, non-destructive, openWorld), so the bar is lower, and the description adds real behavioral context beyond them: result ordering (newest first), page size ceiling (up to 100), the implicit status scoping, and the auth requirement ('Needs the user's Cotlet API key with access to this app'). That auth/prerequisite detail is exactly the kind of thing annotations cannot convey.

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?

It is short and mostly front-loaded, but the first two sentences are redundant, both re-listing 'status, source, contact details and the assigned team member.' Collapsing them into one sentence would lose nothing. Not verbose, but not tight either.

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 does the work of describing the return shape (status, source, contact details, assigned member) plus ordering and pagination, which is appropriate for a simple 3-parameter list tool. Auth requirement is stated. Nothing essential to correct invocation is 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?

Schema description coverage is 100%, so limit, since and status are already documented in the schema, establishing a baseline of 3. The description reinforces the status default and adds the page-size ceiling and result ordering, but adds no syntax or format detail beyond what the schema already provides.

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 second sentence states a clear verb+resource: 'Returns leads, newest first, with status, source, contact details and the assigned team member.' That is enough to distinguish it from the other workiz_* tools (jobs, estimates, invoices, clients), none of which list leads. The opening fragment 'Workiz: Leads with status, source...' is not a full statement of purpose, but the sentence that follows carries it.

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 gives a concrete, actionable default: 'Open is the default, so converted and lost leads appear only when you ask for them,' which tells the agent it must pass status to see converted/lost leads. It does not name an explicit alternative or exclusion, but within Workiz there is no competing leads tool, so no routing guidance is needed.

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