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

Annotations already declare readOnlyHint=true and openWorldHint=true, so safety is covered. The description adds useful scope context ('standard Moodle forums', 'separate, less-commonly-used mod_forum module'), but it does not discuss return behavior, pagination, or privacy constraints beyond what the output schema already provides.

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 compact sentences with zero waste. The primary purpose is front-loaded and the exclusion follows immediately, making it easy to scan.

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 listing tool with a single fully documented parameter, annotations, and an output schema, the description covers purpose and key exclusions. It could be slightly more complete by mentioning the relationship to get_forum_discussions, but no critical information 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 100%, so the course_ids parameter is already documented. The description mirrors that semantics ('across one or more courses') without adding format or validation details, so the baseline of 3 is appropriate.

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 ('List standard Moodle forums') and scopes it to one or more courses. It explicitly distinguishes itself from list_notices/list_qna, so an agent can identify the right tool without opening the 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?

Explicitly says NOT to use this for PLATO's notice/Q&A board and names list_notices/list_qna as alternatives. However, it does not address the closely related sibling get_forum_discussions, which an agent might confuse with listing the forums themselves.

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