postmark_get_delivery_stats

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds value by naming the returned metrics, but omits key behavioral context such as what time window the statistics cover and whether they are scoped per server — information an agent needs to interpret the numbers.

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 front-loaded sentence listing the resource and metrics, with no wasted verbiage. Appropriately sized for a simple getter.

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 and annotations covering only safety, the description should clarify result semantics — most notably the time period the statistics span and their granularity. That gap prevents full completeness for a stats tool, though the listed metrics make it usable.

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?

There is a single api_key parameter with 100% schema description coverage ('Postmark server token'), so the schema fully documents it. The description adds no further param guidance, which is acceptable given the complete schema, but contributes nothing beyond baseline.

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 (get) and resource (delivery statistics) and enumerates the metrics returned (bounces, spam complaints, open rates), so the agent knows exactly what it retrieves. It does not explicitly differentiate itself from postmark_list_templates, postmark_get_template, postmark_search_messages, or postmark_send_email by name, but the resource is clearly distinct.

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 no when-to-use, when-not-to-use, prerequisites, or alternatives among the Postmark siblings. An agent must infer that this is the tool for aggregate delivery metrics; nothing routes it here versus the message/template tools.

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