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

The description does disclose a lot beyond the annotations: section-by-section contents, evidence sourcing, the ads-enabled conditional branch, and a 'guarded preview-first' flow requiring user confirmation. But it explicitly says the tour 'ends with an optional first write ... negative-keyword create,' while the annotations declare readOnlyHint=true and destructiveHint=false; an agent cannot tell whether this call mutates anything, which is exactly the ambiguity annotations are supposed to resolve.

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?

Three sentences, front-loaded with the return payload, then the conditional write, then the positioning disclaimer. The first sentence is dense with a five-item list but every clause carries distinct information; no filler.

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?

For a multi-section read tool with an output schema and read-only annotations, the description covers contents, evidence basis, and the ads-enabled branch well. The one gap is the write/confirm flow, which is described in the result but left unclarified as to whether this invocation performs it.

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% and every parameter (detail_level, evidence_limit, spotlight_count, date_window_days, first_write_min_spend) is documented in the schema with defaults and rationale. The description adds only indirect color ('source-table evidence' hinting at evidence_limit, the spend-without-converting framing behind first_write_min_spend), so the baseline 3 applies.

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?

Names a specific verb and resource and enumerates exactly what the tour contains (trust preflight, account pulse, best-seller spotlight, top movers, cross-domain signals with source-table evidence). It also draws an explicit boundary against a whole class of siblings: 'This is a data/evidence tool, not a recommendation engine,' which separates it from get_bid_recommendations, get_budget_recommendations, and get_brand_health.

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?

'first-run account data tour' establishes the context in which the tool is appropriate, and the ads-key clause states a conditional behavior. However, no alternative or sibling is named as the thing to use instead when this is the wrong choice, so the routing guidance stops short of the top bar.

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