set_daily_budget

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

'PREVIEW ONLY' suggests the tool does not mutate state, but annotations declare destructiveHint=true and readOnlyHint=false, creating a contradiction. Although the description adds valuable guardrails (50% max change, 10,000 cap, 20 actions/day), the core behavioral claim conflicts with the annotation.

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?

Three sentences, no wasted words. Front-loads the preview scope, then lists concrete guardrails, then the approval requirement. Each sentence earns its place.

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 destructive mutation tool with guardrails, the description should clarify whether it actually applies changes or only previews, and how it interacts with confirm_action. It also leaves two of three parameters undocumented. The guardrails help but do not fill these gaps.

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 only 33% (only amount has a description). The description adds budget limits (50%, 10,000) that give meaning to the amount parameter, but campaignId and currency remain completely undocumented with no compensating explanation.

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 ('set') and resource ('daily budget of an Apple Ads campaign'), which distinguishes it from sibling set_keyword_bid. 'PREVIEW ONLY' further scopes the action, though it does not explicitly name alternatives.

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 an explicit condition for applying ('only with the user's explicit approval'), which is a useful guideline. However, it does not state when to use this tool versus alternatives like confirm_action or other ad-management siblings, leaving the workflow context implied.

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