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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered structurally. The description adds meaningful context about the breadth of returned diagnostics (EMQ match-key coverage, freshness, per-group A/B results), which is genuinely useful beyond the annotations. It does not disclose latency, data freshness windows, or rate-limit behavior for external Meta calls, so a 3 is appropriate.

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 dense sentence that front-loads the domain and then enumerates outputs. It is efficient and has no filler, though the parenthetical stacking is slightly hard to parse on first read compared to a short lead plus bullets.

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 an output schema present, the description needn't detail return shapes, and it correctly avoids that. It gives enough topical surface for an agent to know what diagnostics come back. It stops short of telling the agent when this tool is the right call versus its siblings, which is the main remaining gap.

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%, and the schema already documents the `sections` enum and the `account_id` override with defaults. The description mentions the same section categories (opportunity, pixels, catalogs, ab_tests) but adds no syntax, default behavior, or dependency detail beyond what the schema states. Baseline 3 applies when the schema carries the load.

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 names a specific domain (Meta ad account health) and enumerates the concrete outputs: opportunity score with ranked recommendations, pixel EMQ diagnostics, catalog diagnostics, and A/B test results. This is a clear read-oriented verb+resource. It does not, however, distinguish itself from the lookalike diagnostics in query_campaign_performance or creative_report, leaving the sibling boundary slightly ambiguous.

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?

There is no statement of when to reach for this tool versus query_campaign_performance, creative_report, or get_account_context, and no exclusions. For an agent choosing among nine siblings, the description provides no routing signal beyond the topic itself.

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