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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=true, so the safety profile is covered without description help. The description adds no behavioral context such as required ad-account permissions, rate limits, or data-freshness/attribution caveats that a reporting tool would benefit from disclosing.

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?

A single front-loaded sentence that names the verb, the metric list, and the applicable scope with no filler. Every clause earns its place.

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?

There is no output schema, and the description partially compensates by enumerating the returned metrics (spend, impressions, clicks, CTR, CPC, CPM, reach). It is close to complete for a simple reporting tool, though it omits return shape and the default-level behavior when object_id is omitted.

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 all three parameters (level, object_id, date_preset) are already documented with enums and defaults in the schema. The description adds no syntax or format detail beyond what the schema provides, 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?

States a specific verb (Get) plus resource (performance/spend metrics) and enumerates the exact metrics returned. It also scopes the operation to the whole account or a single entity, which cleanly separates it from sibling tools like meta_ads_get_ad or meta_ads_list_campaigns that fetch entity metadata rather than metrics.

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 phrase 'for your whole ad account or one campaign/ad set/ad' implies when the tool applies, but there is no explicit when-to-use guidance or named alternative (e.g., versus meta_ads_get_campaign for structural data). Usage is inferred from the scope rather than stated.

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