Check Bulk Email Readiness

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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=true, so the safety profile is largely covered. The description adds useful scope context: it only checks the targeted recipients and returns guidance rather than sending, reinforcing the dry-run nature. It stops short of saying what failure/unsendable outcomes look like or that it has no side effects on data.

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 tight sentences with no filler; the defining fact (final dry-run gate before bulk email) is front-loaded, and the second sentence covers requirements and 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 gate tool with no output schema, the description says it 'returns sendability guidance' but not the shape or what a negative result implies, and it does not explain kind/threading. Enough to call it, but not fully complete against the 40% schema 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 coverage is only 40%, so the description must compensate. It does clarify recipient_target ('exact IDs or a narrowed selection'), matching the anyOf branches and the most complex param. It says nothing about campaign_id, kind, threading, or requested_parent_wave_id, leaving those documented only partially in the 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 names a specific verb and resource ('check ... readiness', 'final dry-run gate before bulk email') and adds that it checks only the selected recipients and returns sendability guidance. This distinguishes it from the sibling start_bulk_email (which actually sends), though it doesn't name that sibling 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?

It states the condition for use: this is the final gate before bulk email, requiring exact IDs or a narrowed selection. That is a clear usage context with no explicit exclusion list or named alternative, which caps it at 4.

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