List Tag Manager accounts

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

The description adds context about read permissions and the implication of an empty list, going beyond the readOnlyHint annotation. It is consistent with the non-destructive nature and discloses auth requirements.

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 concise (two sentences) and well-structured, conveying the purpose, usage, and interpretation without unnecessary verbosity.

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?

Given the absence of parameters and output schema, the description provides all necessary context: what the tool does, when to use it, and what the result (including empty list) signifies. It also mentions permission requirements, making it complete for the tool's simplicity.

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 no parameters, so the description adds no parameter-specific meaning. The schema coverage is effectively 100% (empty), meeting the baseline for high coverage where additional param info is not necessary.

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 tool lists all GTM accounts readable by the service account/OAuth user, using the verb 'list' and specifying the resource 'GTM accounts'. It also distinguishes from siblings like list_accounts and list_merchant_accounts by focusing on GTM-specific accounts.

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?

Explicitly instructs to use this for first-time discovery before audit_event_coverage and explains that an empty list indicates insufficient permissions, providing clear guidance on when and how to interpret results.

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