Get connected sending domain

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

Annotations already declare readOnlyHint=true and destructiveHint=false. The description adds a non-obvious behavioral detail: 'A profile with no domain connected returns the same shape with every field set to null.' This helps the agent interpret surprising responses and fits the read-only safety profile.

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 sentences, each earning its place: purpose, use-case justification, and null-return caveat plus alternative endpoint. The most important information is front-loaded. No filler or redundancy.

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?

There is no output schema, so the description compensates by summarizing the returned data (verification status, suspended sender addresses) and the null-shape behavior for missing domains. It could list exact field names or error cases, but for a single-parameter read operation with readOnly annotations, it covers what an agent needs 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 coverage is 100%, so the baseline is 3. The description mentions 'connected to the profile' which links profileUuid to the profile entity, but it does not explain how to obtain a valid profileUuid or add beyond the schema's tautological 'Profile uuid parameter' description. No significant extra meaning is provided.

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 opens with a specific verb and resource: 'Get the sending domain connected to the profile, its verification status and any suspended sender addresses.' This clearly defines the tool's output and distinguishes it from the DNS status endpoint, which handles individual MX/SPF/DKIM/DMARC records.

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?

Explicitly states when to use: 'Campaigns only go out once a domain is connected and active, so this is the cheapest way to check that precondition before building one.' It also names the alternative for detailed DNS records: 'use the DNS status endpoint.' These are clear when-to-use and when-not-to-use signals.

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