list_chats

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

Annotations already declare readOnlyHint=true and openWorldHint=true, so safety profile is covered. The description adds genuine value by warning that message reading/sending is out of scope, preventing a mis-invocation. It says nothing about pagination, result ordering, or volume of chat rooms returned, so with an output schema present this is adequate but not rich.

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 short sentences, front-loaded with the action and resource, followed by the critical scope exclusion. No filler or repetition.

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?

Annotations cover the safety profile, the output schema covers return values, and the single parameter is fully documented. The description closes the main risk (agents assuming they can fetch chat messages). A minor gap is the slight wobble between 'chat activities' in the description and 'chat rooms' in the schema, leaving the exact unit returned marginally ambiguous.

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?

Only one parameter with 100% schema description coverage ('One or more course ids to list chat rooms for'), so the schema already carries the semantics. The description's 'across one or more courses' restates the same information without adding format, limits, or behavior for multiple ids. Baseline 3 applies.

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+resource: 'List Chat (real-time chat room) activities across one or more courses', and even defines what 'Chat' means in this API, which disambiguates it from message- or forum-related siblings. It does not explicitly name an alternative tool, but the resource is unique enough in the sibling list that selection is clear.

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 bounds the tool's role: 'Reading/sending chat messages is not supported by this server -- this tool is read-only coverage only.' That is a clear when-not signal that steers an agent away from expecting message content. It stops short of naming which sibling to use for message retrieval, so it falls short of a 5.

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