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

Annotations already declare readOnlyHint, non-destructive and open-world, so the safety profile is covered; the description adds a real behavioral constraint beyond that: a hard cap of 5,000 rows per request and the narrowing strategy. It stops short of disclosing ordering of results, auth requirements, or whether the row cap truncates silently.

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 dense sentences: payload contents first, then the pagination constraint, then the endpoint. No filler and the most decision-relevant fact (5,000-row cap) is front-loaded.

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 six parameters, full schema coverage, annotations and no output schema, the description supplies the missing return-value picture (fields returned) and the row cap. What remains unsaid — result ordering, truncation behavior, and permission requirements — is minor but non-zero for a paginated history endpoint.

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%, including the interval bounds and offset/limit semantics, so the schema does the heavy lifting. The description only reiterates the narrowing trio without adding relationships (e.g., how interval interacts with start_datetime) beyond what the schema states.

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?

States a specific resource (per-lead website traffic history) and enumerates the returned fields (date, page, referrer, IP), plus the underlying endpoint. An agent can tell this apart from siblings like idx_get_lead or idx_list_lead_searches without inspecting any schema.

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 is about how to shape the request (interval/offset/limit) rather than when to choose this tool over alternatives. Usage is inferable — pull visit history for one lead — but no sibling is named and no exclusion or prerequisite is given.

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