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

Annotations already cover safety (readOnly, idempotent, non-destructive, not open-world), but the description adds real behavioral depth: the aggregation windows (4 hours for overall state, 7 days for per-platform rates), the exclusion of content/account failures into a separate customer_side bucket, the explicit degradation behavior ('says so plainly when there is not enough recent activity'), and the privacy guarantee that only aggregates are returned with no post or user data.

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 with the core purpose, then usage triggers, then caveats. Every sentence carries information, but the single paragraph is dense and the closing whoami comparison plus the customer_side caveat could be split for faster scanning.

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 carries the full burden of explaining return content, and it does: overall state, active incident with an example, per-platform state with success rate and counts, plus separate customer_side reporting and the insufficient-data case. Nothing an agent needs to call or interpret this tool is missing.

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 to document and the baseline is 4. The description correctly does not invent parameter detail, and the 'aggregates only, no post or user data' note usefully clarifies that no filtering inputs exist.

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 (check posterly's own publishing health) and enumerates what the result contains: overall state, active incident, per-platform state with 7-day success rate and publish counts. It explicitly distinguishes itself from the sibling whoami view 'status', so an agent can route correctly without opening either schema.

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 concrete triggering conditions — before scheduling a time-critical post, or when a user asks whether posterly or a platform is down or why posts are failing. It also names the alternative (whoami) and the boundary between them, which is exactly the when/when-not guidance the dimension asks for.

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