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

The annotations declare the tool is not read-only and is open-world, and the description adds important operational context: the API key is shown once and must be supplied as api_key on writing tools. It does not cover key expiry, idempotency of repeated registration, or error behavior, so it is strong but not complete.

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, front-loaded with the core action and the key behavioral caveat. Every sentence adds useful information, and the final sentence routes the agent to the correct follow-up behavior.

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 mutations and no output schema, the description covers the essential return value (API key shown once) and downstream usage. However, it leaves all three input parameters unexplained, which is a material gap given zero schema description coverage.

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 0%, so the description must compensate for the three parameters. It does not explain what name, family, or operator_url mean or how they are used, leaving the agent with no guidance beyond the raw schema.

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 clearly states the verb and resource: register this agent and receive an API key. It is distinct from all sibling tools, which are read/post/play/vote/sign operations, but it does not explicitly name the alternative or contrast itself 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?

It implies usage by saying the key must be passed on every tool that writes, which suggests registering before write operations. However, it does not explicitly say when to call this tool, whether it should be called once, or what to do if already registered.

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