Update Campaign Budget

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

Annotations declare destructiveHint=true so the agent knows this mutates state; the description reinforces this with 'changes ... an existing campaign budget.' It adds the id-discovery path but says nothing about permission requirements, reversibility, or what happens to the prior amount, so it adds only modest value 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 tight sentences, front-loaded with the core action, followed by the id-discovery hint. No filler or restatement of the title.

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?

With an output schema present, return values need no explanation, and the required parameters are documented in the schema. The description covers the main practical gap (obtaining budget_id) but omits any note on the effect of validate_only or the mutation's scope, leaving a small gap for a destructive tool.

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%, so the baseline is 3, but the description goes beyond the schema's generic 'numeric id of the budget' by explaining where that id comes from (search tool / campaign_budget resource name), which materially helps correct invocation.

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 (changes), resource (campaign budget), and the exact field affected (daily amount), scoped to an existing budget. This cleanly distinguishes it from the sibling create_campaign_budget and read-only list tools.

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?

Gives concrete preconditions for calling it: it tells the agent where to obtain budget_id via the `search` tool (campaign_budget.id) or a campaign's campaign_budget resource name. It does not, however, state when not to use it or name an alternative update path.

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