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

Annotations already declare readOnlyHint/destructiveHint/idempotent, so the safety profile is covered. The description adds genuine behavioral context beyond them: the dashboard is interactive with in-window tabs, payments/ROAS load into it, and the agent must not pre-read the numbers. It does not explain pagination or latency, but this is a rendering tool.

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?

Front-loaded: the resource and its contents come first, then the trigger, then the 'do not read first' rule, then the free/read-only note. It is a dense run-on sentence, but nearly every clause carries distinct information, so the length is largely earned.

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 zero-required-param, read-only rendering tool with no output schema, the description covers what is shown, when to invoke it, and how to avoid redundant reads. Minor gap: it does not note that a connection/ad account must be disambiguated when several are linked, though the schema covers that.

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 100%, so the baseline is 3. The description still adds meaning by tying the 7/14/30/60/90 tabs to the day window the person switches, and by explaining that payments/ROAS load into the dashboard (the purpose of `part`, which the schema tells you to leave out). This is context the schema does not carry.

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+resource: renders an interactive dashboard of ONE Meta ad account, and enumerates exactly what it shows (spend, results, cost per result, link CTR, CPM, daily chart, campaigns, payments/ROAS). It is clearly distinguishable from siblings like performance_overview, show_dashboard and meta_ads_read.

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?

Gives an explicit trigger ('when the person asks how their ads are doing, or for a dashboard, overview or report of an ad account') plus a strong procedural rule ('it reads the numbers itself: do not read them first'). It never names the alternative tools it should be picked over, so the when-not/alternative half is missing.

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