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

With no annotations supplied, the description carries the full behavioral burden. It discloses that the tool creates an identity, returns an api_key and mcp_url, embeds the key in the URL, and supports Bearer-token authentication for subsequent tools. It does not discuss key sensitivity, irreversibility, rate limits, or error behavior, which keeps it from a 5.

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?

The description is two tight sentences with no wasted words. The core action and return values are front-loaded, followed immediately by the authentication instruction.

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 no output schema and no annotations, the description covers the essential lifecycle: create the identity, receive credentials, and use those credentials for other OpenMoney tools. It could be stronger by mentioning security handling of the key or whether registration is idempotent/recoverable, but it is otherwise complete enough to invoke correctly.

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 high at 86%, so the schema already explains most parameters, including name, contact, sandbox, platform, use_case, developer, and owner_label. The description adds no parameter-level meaning beyond what the schema provides, which is the expected baseline when the schema does the heavy lifting.

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 uses a specific verb ('Create') and resource ('OpenMoney agent identity'), and it also states the key output of the operation. An agent can immediately understand that this is the registration/bootstrap tool rather than a general-purpose OpenMoney action.

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 clearly explains what to do after registration: reconnect to the returned mcp_url or send the api_key as a Bearer token to use the other OpenMoney tools. There are no sibling tools to compare against, but the description does not explicitly state prerequisites or when not to call it, so it stops short of a 5.

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