Connection health check

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

Annotations already declare readOnlyHint, openWorldHint, and non-destructive, so safety is covered. The description adds genuine behavioral context beyond that: the exact services probed, the conditional Reddit check, and that it returns per-service status plus actionable remediation guidance. It does not mention rate limits or auth prerequisites, keeping it out of the 5 band.

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?

The purpose and diagnostic framing are front-loaded and the sentences earn their place. However, the three trailing API documentation URLs are long and expend little value for an agent deciding whether to call the tool, slightly diluting an otherwise tight definition.

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 need not detail return values, and it still summarizes them as per-service status plus remediation guidance. For a zero-parameter diagnostic, everything an agent needs to select and call it correctly is present.

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?

The tool takes zero parameters, so there is nothing for the description to disambiguate; the 0-param baseline of 4 applies. The description correctly implies no arguments are needed to invoke it.

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 and resource ('Test AdLoop connectivity') and enumerates exactly what is checked: OAuth token, GA4 API, Google Ads API, and conditionally Reddit Ads API. This distinguishes it cleanly from siblings like validate_tracking or get_merchant_feed_health, which check specific objects rather than overall connectivity.

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?

Explicitly frames itself as 'the diagnostic for failures in other tools,' which tells the agent when to reach for it. It stops short of naming specific alternative tools or stating when-not to use it, so it falls just under the top band.

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