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

Annotations only say it is a non-destructive, open-world write; the description adds real behavioral value by disclosing the human email-confirmation requirement, the Secretariat review gate, and the returned identifiers. It stops short of covering idempotency or what happens if the domain is already registered.

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, no filler, and the action plus return values are front-loaded before the confirmation workflow.

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 an 11-parameter mutation with no output schema, the description covers the outcome (application_id, verification token, next steps) and the post-call process, which is what an agent most needs. Remaining gaps are edge-case behavior such as duplicate applications or what to do if email confirmation never occurs.

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 coverage is 55%, so the schema documents roughly half the inputs. The description reinforces the most consequential one ('contact_email must be a real person at the brand who confirms by email') and the brand scope behind organisation/domain, but says nothing about agent_name, lang, category, country, markets or job_title. Baseline 3 fits.

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 with scope: 'Apply for free CGBB membership on behalf of a brand', and names the artifacts produced (application_id, domain-verification token, next steps). Differentiation from siblings like get_application_status is implicit via the described workflow rather than stated explicitly.

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 eligibility context ('a real person at the brand must confirm by email') and the Secretariat review step imply when this tool applies, but there is no explicit when-to-use/when-not guidance and no named alternative (e.g., checking an existing application first).

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