google_ads_bid_adjustments_update

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

Describes mutation, FieldMask-based partial update, reversibility, valid range, and error behavior (ValueError). Since no annotations are provided, the description fully covers behavioral traits.

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?

Concise and well-structured: action, return, behavior details, constraints, alternative. Every sentence adds value without redundancy.

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?

Complete for an update tool: describes return value, mutation behavior, parameter constraints, and alternative tool. No output schema needed; the description suffices.

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%, but the description adds significant meaning: explains bid_modifier values (0.1=-90%, etc.), range rejection, and that customer_id falls back to environment variables, which the schema does not fully convey.

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?

Clearly states it updates the bid_modifier of a single campaign_criterion and returns the resource_name. Distinguishes from sibling tools by explicitly naming google_ads_device_targeting_set for toggling devices with 0.0 bid_modifier.

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?

Provides explicit guidance: when to use this tool for updating bid_modifier and when to use an alternative (google_ads_device_targeting_set) for toggling devices. However, does not cover other scenarios like when not to use it generally.

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