canvas_announcements

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

With no annotations, the description carries the full behavioral burden. It usefully discloses result ordering (newest first) and the default scope when `course` is empty, but says nothing about authentication requirements, pagination, or result limits. An output schema exists, so return shape is covered elsewhere, keeping this at an adequate 3.

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?

A single sentence, front-loaded with the resource and ordering, followed by the two scoping cases. No filler and no restatement of the tool name.

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 two-parameter read tool with an output schema, the description covers purpose, scope branching, ordering, and both parameters' semantics. The only omission is auth/pagination behavior, which is minor given the schema already defines return values.

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%, so the description must compensate, and it largely does: `days` is defined as the lookback window and `course` is described as accepting an id, a code, or a partial name, with the empty-string case meaning all current courses. It omits the default value of `days` (14), which the schema supplies.

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 resource (announcements), a time window (last `days` days), an ordering (newest first), and the two possible scopes (one course vs. every current course). No sibling tool covers announcements, so there is no ambiguity to resolve, and an agent knows exactly what it will get back.

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 implicitly tells the agent when to use each mode: pass a course value for a single course, leave `course` empty for a cross-course sweep. It gives clear context but names no exclusions or alternative tools (e.g., nothing about when to prefer canvas_deadlines or canvas_courses instead).

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