announce

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

With no annotations provided, the description must carry the full burden of behavioral disclosure. It explicitly states 'WRITES TO MOODLE and emails everyone enrolled,' which reveals the mutation and the mass-email side effect. The caution to check wording also adds context. It doesn't detail reversibility or permissions, but the core side effects are transparent.

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 two sentences with zero waste. The first sentence front-loads the critical side effects, the second gives the purpose and a user-safety caveat. Every word earns its place, and it's structured for quick scanning.

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 simple mutation tool with no output schema, the description is adequately complete. It states the action, the side effect, and a necessary user check. It doesn't mention prerequisites like permissions or how to obtain course IDs, but those are either implied or covered in the schema. The omission of an explicit 'who can call this' is a minor gap.

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 schema description coverage is 100%, with all four parameters individually described. The tool description does not add additional parameter semantics beyond what the schema provides, which is expected given the high coverage. It doesn't compensate for any gaps, but none exist here, so a baseline 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?

The description clearly states the action: 'Post an announcement in the course's news forum' and adds that it emails everyone enrolled. It specifies the verb and resource, distinguishing it from the sibling 'announcements' which likely reads announcements. However, it doesn't explicitly name alternatives, so it falls short of a 5.

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 provides no guidance on when to use this tool versus alternatives. It includes a caution to check wording with the user, but that is a pre-call confirmation, not a selection criterion. No exclusions or alternative tools are mentioned, leaving the agent to infer when to use it.

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