chat_capabilities

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

No annotations are provided, so the description carries the full burden. It discloses that the tool reports documented support, missing features, and a proposed future contract, and that it is advisory before implementation work, but it does not state read-only safety, auth needs, or rate limits. The output schema can cover return details.

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 tight sentences with no waste. The main purpose is front-loaded, and the usage context follows immediately without redundancy.

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 zero-parameter capability-reporting tool with an output schema, the description is mostly complete: it says what it reports and when to call it. It could be stronger by explicitly relating itself to runtime_capabilities or clarifying that the output is advisory, but no critical agent need 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?

The tool has zero input parameters, so there are no parameter semantics to document. The empty schema is fully covered, and the baseline for zero params is 4.

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 reporting action and names the areas covered: documented chat support, missing formatting features, and a proposed future API contract. It is clearly chat-specific, distinguishing it from runtime_capabilities in practice, but it does not explicitly name or contrast with that sibling.

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 explicit pre-call guidance: call before building chat tags, command suppression, rich text, team-colored player names, segmented messages, or send-as-player behavior. It does not state when not to use it or name an alternative tool, but the usage context is clear.

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