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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=true, so the safety profile is covered. The description adds value beyond that by disclosing the return fields, newest-first ordering, and an auth requirement (a Cotlet API key with app access), which the annotations do not convey.

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 short and front-loads the resource and key attributes. The 'channel, subject and delivery status' content is stated twice across sentences and the redundant 'DoorLoop:' prefix adds little, so it is efficient but not perfectly tight.

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 return-value burden and does so by naming the fields and ordering. Combined with the auth note and usage hook, an agent has enough to call it correctly, though pagination behavior beyond the cursor param is unstated.

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 100%, so both the 'since' filter and 'cursor' pagination are already documented in the schema. The description reinforces time-ordering but adds no new meaning about these parameters, making the baseline 3 correct.

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 names a specific verb (list) and resource (the Communications Log) and states exactly what the entries contain (channel, subject, delivery status) and their ordering (newest first). It also names a sibling tool (send_announcement), so an agent can distinguish it from write operations without opening a 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?

It gives explicit usage context: 'Use it after send_announcement to see who the announcement reached,' which ties the read to a prior action. It lacks any when-not-to-use or alternative listing tools, but the positive guidance is clear and actionable.

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