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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description adds a genuine behavioral fact beyond that: these recipients are account-level and shared across all products regardless of the active one, which matters for interpreting the result.

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 tight sentences, front-loaded with the definition of the resource before the scoping constraint and the use case. No filler or restatement of the name.

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?

With no output schema, the description compensates by stating what the items are (email addresses), and the account-level scope note prevents a false assumption about per-product filtering. It does not mention ordering, count, or what an empty result means, which is a minor gap for a list endpoint.

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 tool takes no parameters (empty schema, additionalProperties false), so there is nothing for the description to disambiguate. Baseline for a zero-parameter tool; no misuse risk from arguments.

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 (List) and resource (saved test recipients), then disambiguates the resource from the similarly named contacts list by defining it as 'the email addresses you send preview/test emails TO'. Unambiguously separable from siblings like meisa_list_contacts, meisa_list_senders and meisa_list_templates.

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?

Gives concrete when-to-use guidance: 'find an address before sending a test, or to review who test emails go to.' That covers the primary intent, though it does not name the sibling actions that consume this list (e.g. meisa_send_template_to_test_recipients) or note that add/delete_test_recipient exist as alternatives.

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