email_forward_list

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

With no annotations, the description carries the full burden. The verb 'List' clearly indicates a read-only operation, which is a key behavioral trait. However, it provides no additional details about pagination, error conditions, or the exact structure of the response, leaving some ambiguity.

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 description is a single, front-loaded sentence with no filler. It earns its place by directly stating the operation and scope, making it appropriately concise.

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 simple one-parameter list tool with no output schema, the description is sufficient for correct invocation. It clearly defines the input scope. A minor gap is the lack of any mention of what the returned rules contain, but this is not critical for tool selection.

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?

The schema fully documents the only parameter 'domain' with a description and example, so schema coverage is 100%. The description adds no extra meaning beyond repeating 'domain', thus the baseline 3 applies.

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 'List all email forwarding rules configured for a domain' clearly specifies the verb (List), resource (email forwarding rules), and scope (for a domain). It is distinct from sibling tools like url_forward_list (URL forwarding) and email_forward_add/update/remove (mutations).

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 description implies usage: use when you need to see email forwarding rules for a domain. However, it does not explicitly state when not to use it or mention alternatives, leaving the agent to infer context from the sibling tool names.

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