list_accounts

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, establishing a safe read-only operation. The description adds context about the default account behavior ('which one is used when a tool call does not name one'), which is valuable beyond the annotations. However, it doesn't describe the return structure or list format, which is a minor gap.

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 sentences with no redundant words. The first sentence states the primary function and a key behavioral detail, the second explains the switching mechanism. Every word earns its place, and the description is appropriately sized for the tool's simplicity.

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 parameterless, annotation-rich tool, the description fully covers what an agent needs: what the tool lists, the default account behavior, and how to change accounts. No output schema exists, but the purpose is simple enough that return format is self-evident. Nothing essential 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?

The tool has zero parameters, and schema description coverage is 100% (empty schema). The baseline for 0 params is 4. The description mentions the `account` argument as a cross-tool concept, which adds context even though it's not a parameter of this tool. No deduction needed.

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 uses the specific verb 'List' and clearly identifies the resource ('Google accounts this server can act as'). It also distinguishes its purpose from the sibling tools by focusing on account management rather than site operations, making the tool's role immediately clear.

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 explains when to use the tool (to discover available accounts and the default account) and provides explicit instructions for switching accounts via the `account` argument on other tools. This gives clear context for usage relative to alternatives without needing to reference sibling tools.

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