blackboard_list_discussion_messages

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

Annotations already cover readOnly, idempotent, and non-destructive, so the bar is lower. The description adds genuinely new behavior: it respects Blackboard group/permission scoping and does NOT mark messages as read — a side-effect note the annotations cannot express.

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?

Three short, dense statements with zero filler; the default-value fact and the onlyMine behavior are front-loaded before the permission caveat.

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 read-only list tool with no output schema, the description covers scoping, default filtering, and side effects. It omits pagination/result-size behavior, but nothing required to invoke it correctly 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?

Schema description coverage is 0% across 5 parameters, but courseId, discussionId, and groupId are self-describing. The description disambiguates onlyMine and states the status default, yet leaves the Deleted/Draft enum values and the groupId pattern unexplained.

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?

Names a specific verb+resource ('Mensajes accesibles de una discusión Ultra'), and specifies the default scope ('publicados por defecto'). It implicitly distinguishes a message listing from sibling blackboard_list_discussion_replies, but never names that sibling or clarifies the boundary explicitly.

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 useful selection context: default status is 'Published' and onlyMine narrows to the current account. However, it never says when to prefer this over blackboard_list_discussion_replies or blackboard_get_discussion, so the agent must infer routing from tool names alone.

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