Add callouts

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

Annotations already indicate non-read-only and non-destructive. The description adds valuable context about immutability, which is not captured in annotations. Could have mentioned potential duplicate handling or side effects, but overall adds good transparency beyond annotations.

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 concise sentences with no fluff. Essential information is front-loaded: creation action, character limit, immutability, and assignment hint.

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 tool's simplicity (one parameter, no output schema), the description fully covers creation, immutability, character limit, and assignment context. No gaps remain.

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?

Schema coverage is 100% with one parameter 'texts'. The description reinforces the character limit (scheme has maxLength) and adds that these are callout texts that are immutable. While the schema provides the constraint, the description gives semantic meaning to the parameter.

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 'creates' and the resource 'callouts', with a specific constraint of up to 25 characters. It distinguishes from siblings like delete_callouts and get_callouts by noting immutability and the need to use the Ads service for assignment.

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 states that callouts are immutable and to change them one must delete and recreate. Also clarifies that this tool only creates the callout objects, not assigning them, directing the agent to the Ads service for assignment.

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