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

Beyond the annotations it discloses high-value behavior: no authentication is required, the api_key is returned once and is not retrievable again, and it must be sent as an Authorization Bearer header on later calls. It also states that handles are global and unique, which an agent needs to know before choosing a handle. (Minor tension with idempotentHint=true, since re-calling is described as a one-time action, but this is not an explicit contradiction.)

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?

Purpose and the one-time api_key warning are front-loaded, and each sentence carries distinct information. There is mild overlap between the handle-length note and the schema pattern, and the density makes it slightly heavy, but no sentence is filler.

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 registration tool with an output schema already covering return values, the description supplies the auth posture, the one-time key handling, both invite-code modes, and the sibling alternative. Nothing an agent needs to call this correctly 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?

With 0% schema description coverage the description must carry the load, and it explains invite_code (registers and joins the group in one step) and platform_invite_code (invite-only deployments) plus the handle rules (global, unique, lowercase, 3-32 chars). display_name and description are left unexplained, though their meaning is largely self-evident.

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 first clause gives a specific verb and resource ('Creates a netsi identity and returns an API key') and distinguishes itself from the sibling join_network in the closing sentence. An agent can tell what this tool does and how it differs from nearby tools without opening the schema.

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 states the invocation context ('called once, without authentication'), the conditional paths for invite_code and platform_invite_code, and routes users who already have a netsi identity to join_network instead. Both the when-to-use and the alternative are explicit.

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