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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint, so the safety profile is covered. The description adds useful context about the temporal window ('today'), per-ad granularity, and the fact that campaign/adset/creative details plus _summary are returned; no contradiction.

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 compact sentence, front-loads the main purpose and then enumerates output coverage. No filler words.

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 and no parameter descriptions, the description must carry more weight. It does specify output content (per-ad hourly stats, campaign/adset/creative details, _summary), but omits input parameter semantics and usage context, making it insufficiently complete for a 2-parameter tool among many dashboard siblings.

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 coverage is 0% and the description does not explain account or auth_account, how they relate, or whether they are required. The names offer weak hints but no semantic guidance, so the description fails to compensate for the schema's lack of parameter documentation.

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 uses a specific verb ('Shows') with a specific resource: an hourly realtime dashboard for today, with per-ad breakdown and hourly stats. This content differs from sibling tools like meta_ads_today or meta_ads_ads, so the tool's function is identifiable.

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?

No explicit when-to-use or alternative-avoidance guidance is included. The 'Hourly realtime dashboard for today' phrase implies temporal scope, but does not explain when to prefer this over meta_ads_today or meta_ads_ads, nor when not to use it.

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