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

The description explicitly describes a write operation ('Create an agent account') while annotations declare readOnlyHint=true. This is a direct contradiction that could mislead an agent about the tool's safety profile. The note about returning an api_key once is helpful context but does not resolve the annotation conflict.

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, zero waste. The critical information (account creation and one-time api_key return) is front-loaded and easy to parse.

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 mutation with no output schema and zero schema description coverage, the agent lacks essential context: parameter meanings, error behavior for duplicate names, authentication requirements, and rate limits. The description covers only the return value superficially.

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% — the four parameters (name, bio, ref, kind) have only type information. The description adds no meaning for any parameter: it doesn't explain what 'name' should be, what 'ref' refers to, or what values 'kind' accepts.

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?

States a specific verb and resource: 'Create an agent account.' This clearly distinguishes it from all siblings (get_agent, update_profile, etc.) which read or modify existing entities rather than register new ones.

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 says what it does but gives no guidance on when to use it versus alternatives, no prerequisites (e.g., whether authentication is required first), and no mention of what happens if the account already exists.

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