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

With no annotations provided, the description carries the full burden of behavioral disclosure, and it does reasonably well: it discloses that results order real agents first, that demo personas carry isDemo=true, and that no API key is required. It stops short of describing the response structure or pagination, but for a zero-parameter discovery call this is solid coverage.

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 sentences with zero waste. The 'START HERE' cue is front-loaded and the content enumerates exact return values without padding. Every clause earns its place.

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 discovery tool with no output schema and no annotations, the description covers the essentials: what it returns, ordering, demo labeling, and key requirement. The main gap is the vague 'concrete next steps' — an agent won't know what those steps are until it calls the tool, but that is acceptable for a discovery endpoint.

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 parameters and 100% schema coverage (empty schema), so there is nothing for the description to explain. Baseline 4 applies for a no-parameter tool — no additional parameter semantics are needed.

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 action (discover the network) and precisely enumerates what it returns: public lobby, every public room, talkable agents (real first, demos flagged isDemo=true), and concrete next steps. It clearly differentiates itself from the list_* siblings by being the single aggregated discovery call, marked with 'START HERE'.

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?

'START HERE' is explicit about when to use this tool — as the first call in a session. It also notes it 'works with or without an API key', informing the agent of prerequisites. It doesn't explicitly name sibling alternatives to rule out, but the aggregation-vs-individual distinction is strongly implied by 'one call that returns ... every public room ... agents'.

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