Change ad group budget

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

Beyond the idempotentHint annotation, the description explains that the budget value replaces the current budget rather than adding to it, making repeat calls safe. It also discloses that the API rejects non-manual groups, returns acknowledgement plus apiPointBalance, and cannot pause/resume/delete a group—providing valuable behavioral context 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?

The description is well-structured and front-loaded with the primary action. Each sentence adds necessary information—purpose, replacement behavior, constraints, limitations, and prerequisites—without redundancy or excessive length.

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 moderate complexity, the description fully covers return values (acknowledgement plus apiPointBalance), prerequisites (read list_groups first), and edge cases (manual bid only). With no output schema, this return value disclosure is essential and provided. The description is complete for agent decision-making.

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 descriptions for both parameters, so the baseline is 3. The description adds extra meaning by specifying the groupId comes from list_groups, reinforcing the budget unit (rubles) and minimum, and noting the manual bid constraint. This goes beyond the schema, justifying a 4.

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 sets one ad group's budget to a given amount in rubles, with a specific verb, resource, and scope. It explicitly distinguishes itself from sibling tools by stating it cannot change campaign budget, bid, or group status, and points to change_group_price for bids.

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 description provides explicit when-to-use guidance: only for ad groups on manual bid management, and directs users to read the current budget with list_groups first. It also clearly excludes alternative uses (campaign budget, bid, status changes) and names the alternative tool for bid changes.

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