list_campaigns

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

With no annotations, the description carries the burden. It does make the read-only nature clear via 'List' and states the default limit behavior, but it does not disclose pagination, ordering, return shape, or what a null status_filter means. Adequate but incomplete.

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?

Core sentence is front-loaded and the Args list is compact. It loses a point only because the Args section partially duplicates schema defaults rather than adding entirely new structure.

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 list tool with no output schema, the description covers invocation parameters and default behavior, but it omits return value shape, pagination/ordering, and the exact customer_id format. It is sufficient for basic use, not fully complete.

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 Args block adds meaning absent from the schema: status_filter allowed values ('ENABLED'/'PAUSED'/'REMOVED'), limit's max-return behavior and default, and customer_id's purpose. The customer_id explanation is thin, which keeps this from a 5.

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 ('campaigns in a Google Ads account'), and the plural 'campaigns' plus 'list' separates it from get_campaign. It does not explicitly contrast with sibling tools, so it stops short of 5.

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 intended use is implied by 'List campaigns' and the optional status_filter/limit arguments, but there is no when-to-use guidance, no exclusions, and no mention of get_campaign or get_campaign_performance as alternatives. Context must be inferred from tool name and sibling list.

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