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

With no annotations provided, the description must disclose behavior. It clearly states this is a read-only diagnostic tool (showing coverage/lag) and hints at its role in checking data readiness. It doesn't disclose potential issues like rate limits or whether it only returns data for zones/endpoints with activity, but the core behavior is transparent.

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 description is a single, efficient sentence that packs a lot of information: what it shows, the granularity, and when to use it. No wasted 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?

For a diagnostic read-only tool with 2 optional parameters and no output schema, the description is fairly complete. It tells the agent what the tool does and when to call it. The gap is that it doesn't describe the return format or what specific coverage/lag metrics are included, but this is somewhat mitigated by the tool's apparent simplicity.

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 0%, so the description should compensate for the two parameters (zone and endpoint). The description mentions both 'endpoint × zone' in the context of what is shown, which implicitly defines what the parameters filter by. However, it doesn't explain how the parameters interact (e.g., are both required? what happens if one is null?), leaving some gaps in parameter semantics.

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 states a specific verb ('Show'), a concrete resource ('ingest coverage and lag'), and a clear granularity ('endpoint × zone'). It doesn't explicitly differentiate from sibling tools, but it provides enough specificity about what is shown to make the tool's purpose clear.

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 description gives an explicit usage directive: 'call before queries if you're not sure whether the data is landed yet.' This is clear, actionable guidance on when to use the tool, effectively setting expectations for its purpose.

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