List Announcements

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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, openWorld), and the description adds genuinely new behavior: newest-first ordering, the implicit 30-day window, and the important warning that bodies are fenced as untrusted text. The 'Read-only' sentence is redundant with the annotations, which keeps it from a 5.

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 sentences with zero filler: purpose and ordering first, then safety semantics, then parameter defaults. Everything is front-loaded and every clause carries information.

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 does the work of naming returned fields, ordering, and the untrusted-body handling, which is sufficient for a read-only list tool. It doesn't explain how 'limit' interacts with results or pagination/truncation behavior, a minor remaining 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?

Schema coverage is 100%, so the schema baseline is 3. The description still adds meaning by disclosing the 30-day default window for start_date/end_date, which the schema does not state, while the course_ids default is already documented in the schema.

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 states a specific verb and resource ('List announcements from one or more courses'), adds the returned fields and sort order, and is clearly distinct from discussion siblings like list_topics or list_conversations. An agent can identify the tool's function 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?

It gives concrete calling context through defaults: omitting dates yields the last 30 days, and omitting course_ids spans all active courses. It names no explicit alternative or exclusion, so it falls short of the 5 bar, but the defaults remove most ambiguity about when and how to invoke it.

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