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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the description's main behavioral addition is the word 'active', implying it returns the currently configured provider rather than a historical or candidate one. This adds some context but does not describe response formatting or edge cases.

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?

One short, front-loaded sentence with no redundant words. Every part earns its place by specifying action, scope, and state.

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 zero-parameter, read-only lookup with an output schema and annotations covering safety, the description is sufficient. It could be slightly more explicit about what 'email provider' encompasses, but no critical calling information is missing.

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?

There are no parameters and schema coverage is trivially 100%, so the baseline is 4. The description adds the meaning that the provider is tied to 'the account', making it clear the tool operates on the current account context without requiring explicit input.

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 clearly states the verb 'Get', the resource 'email provider', and a specific modifier 'active' scoped to 'the account'. This distinguishes it from sibling tools like set_email_provider, list_email_domains, and get_email_template.

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?

No explicit when-to-use or alternatives are given, but the action verb 'Get' and the contrast with sibling set_email_provider implicitly signal this is the read-only retrieval counterpart. There are no exclusions or prerequisites stated.

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