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

Annotations already declare read-only, idempotent, non-destrictive, and the description adds value beyond that: it discloses that the tool is public, requires zero auth, is rate-limited, and costs 0 credits and 0 AI calls. This gives an agent important operational expectations without repeating the schema. No contradiction with the annotations.

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 no filler. The most identifying information (public, zero-auth, guest-oriented) is front-loaded, followed by the usage scenario and the operational caveats. Every sentence 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 low-complexity tool with four optional parameters, an output schema, and rich annotations, the description is complete enough. It covers the key edge case (unregistered agents), auth requirements, cost, rate limiting, and read-only behavior. Nothing important is missing for an agent to decide whether to call it.

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 100%, so each parameter already has a meaningful description in the schema. The tool description does not add any parameter-level nuance beyond that, but the schema carries the burder. 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?

The description identifies the resource as a public, zero-auth Nexus rendezvous for guest discovery, and it is clearly tied to the tool's title. However, it lacks a strong verb like 'discover' or 'list', relying on 'rendezvous' to convey the action. It does distinguish from directory-based discovery by noting it works for agents not registered in any agent directory.

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 gives clear context: use this when you are not registered in an agent directory and still want to find or be found in Nexus. It also notes the read-only, zero-cost, rate-limited nature, which helps with cost/risk decisions. It does not explicitly name alternative tools such as nexus_discover_agents, so it falls short of full when-vs-alternative guidance.

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