Dashboard counts

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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so safety is covered. The description adds the meaningful behavioral detail that the counts span the whole instance (no filtering), but says nothing about cost, caching, or freshness of the totals.

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 sentence, front-loaded with the scope ('across the instance') followed by the counted categories. No wasted words; only slight terseness prevents a 5.

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, the description compensates by naming the return contents (subscribers by status, lists, campaigns, messages). Combined with annotations covering safety and idempotency, an agent has enough to call it correctly; exact field names would be nice but are not essential.

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 the baseline is 4. The description correctly implies no scoping/filter input is possible, consistent with the empty schema.

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 resource (dashboard totals) and enumerates what is counted: subscribers by status, lists, campaigns, messages. This distinguishes it from listing tools like lists_list or campaigns_search, though it doesn't explicitly say 'returns aggregate counts only, not records'.

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?

Usage is implied by 'Totals across the instance' — an agent can infer this is the summary/statistics tool rather than a listing tool. However, no explicit when-to-use guidance or named alternatives (e.g. use lists_list for per-list details) are given.

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