list_accounts

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

With no annotations provided, the description carries the full transparency burden. It discloses that the tool returns 'every accessible customer ID' and marks allowlisted ones, providing meaningful behavioral detail about the output. Since it's a read-only list operation, no side effects are expected, and the description adequately covers the behavior without needing to mention auth or rate limits.

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 extremely concise—two sentences that get straight to the point. The first sentence states the action, and the second describes the output. Every word earns its place with no fluff, making it easy for an agent to parse quickly.

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, zero-parameter tool with an output schema, the description is complete. It explains what the tool lists and the specific detail about allowlisted accounts, which is the key differentiator. The output schema likely handles return format details, so the description doesn't need to elaborate further.

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, so there are no parameter semantics to elaborate. The description covers all necessary context about what the tool returns, which is sufficient given the absence of parameters. The empty schema means 100% coverage, but the description adds value by explaining the output's meaning.

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 'List' and the resource 'Google Ads accounts these credentials can reach,' immediately conveying what the tool does. It also distinguishes itself from sibling tools like list_campaigns by specifying 'accounts' and the 'accessible' scope, making it unambiguous.

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 provides clear context by explaining it returns all accessible customer IDs and highlights allowlisted accounts. While it doesn't explicitly mention when to use it over alternatives or exclusions, the purpose is obvious from the description, and no specific alternative is needed for a zero-parameter listing tool.

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