blackboard_list_messages

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

With no annotations, the description carries the behavioral burden. 'Read' clearly signals a non-mutating operation, and 'complete conversation threads ... including all messages and embedded file attachments' discloses that the tool returns full thread content rather than summaries. It does not mention authentication or error behavior, but for a read-only listing tool the core transparency is present.

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?

Two sentences with no waste: the first front-loads the action, resource, scope, and depth of content, while the second states the optional filter. Every clause earns its place.

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 tool with three optional parameters and no output schema, the description is largely sufficient: it states exactly what is returned and the available filter. It does not describe the response shape or pagination, but the schema already documents limit/offset defaults, making these minor gaps.

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 input schema has 100% description coverage for all three parameters, so the baseline is 3. The description adds only a restatement of the optional courseId filter and does not enrich the meaning of limit or offset beyond what the schema already provides.

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 uses a specific verb ('Read') and names a precise resource: complete conversation threads in the current student's Blackboard inbox. It also clarifies that embedded attachments are included and that results can be scoped by course, which separates it from discussion-board tools like blackboard_list_discussion_messages.

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 clear context for when this tool is relevant: reading inbox conversation threads, optionally for one course. However, it never explicitly states when not to use it or names alternatives such as discussion-message tools, so an agent must infer routing from the word 'inbox' rather than being directed.

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