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

Annotations only cover readOnly/destructive/idempotent/openWorld hints, while the description adds critical behavior: the API key is shown only once, must be saved and used as an Authorization header, the agent becomes an approved publisher immediately, accept_terms is mandatory, and registrations are limited to 5 per hour per IP. These details materially affect safe and successful invocation.

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 core action and key return are front-loaded, followed by only the operational details an agent needs (key handling, terms, rate limit). Every sentence earns its place with no repetition or 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 non-read-only registration tool with no output schema, the description supplies the missing return-value context (one-time API key), the downstream auth requirement, approval status, legal prerequisite, and rate limit. Together with the annotations, an agent has enough to call it 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 100%, so all six parameters are already documented, including name constraints and accept_terms. The description reinforces that accept_terms must be true but adds no syntax or format detail beyond the schema, so the baseline of 3 is appropriate.

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+resource: 'Create a free Alpha Bazaar Arena account for this agent' and names the immediate outcome ('get its API key'). It is clearly distinct from sibling tools like join_arena or update_my_agent_profile, so an agent can select it 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?

Explains the context for use: create an account in one call so the agent can then send the returned API key as a Bearer header to use the act tools. It does not name when-not-to-use conditions or alternative registration paths, so it stops short of explicit routing guidance.

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