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

Annotations already declare readOnlyHint/idempotent/non-destructive, so the trailing 'Read-only' adds nothing. Beyond that, the description discloses meaningful behavior: results are ordered worst first, each row carries open guardrail signals with reasons, cover days, next inbound PO, POAS with 1.0 = break-even, ACoS vs break-even, and what SKU.io has paused or throttled. With no output schema, that result-content disclosure is genuinely useful.

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?

One dense sentence with the purpose front-loaded before a colon-delimited field list; every clause carries information. It borders on over-packed, but nothing is redundant.

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 7-parameter read tool with no output schema, the description covers purpose, ordering, and returned content well, and annotations cover the safety profile. It still leaves the agent without sibling routing guidance and without explanation of the health/signal_type filter vocabulary or default result limits.

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 the schema already documents sku, limit, health, platform, product_id, signal_type, and only_with_signals, making 3 the baseline. The description adds no filter semantics beyond what the schema states and does not clarify the default behavior of only_with_signals (implicitly true from 'open guardrail signals') or how filters interact.

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 states a specific resource and angle: advertised products whose ads waste money on stock or margin, ranked worst first, with named output fields (POAS, ACoS vs break-even, cover days). That is far more specific than the name 'get_ad_health' alone. It does not explicitly distinguish itself from siblings like get_ad_performance or get_ad_recommendations, so it stops short of a 5.

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 'worst first' framing and 'waste money' scope imply a triage use case, which is useful implied guidance. However, it never says when to use this instead of get_ad_performance, get_ad_recommendations, or explain_ad_change, and offers no exclusions or prerequisites.

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