update_sd_campaign_budget

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

With no annotations, the description carries full burden. It discloses 'guarded write' and 'preview' behavior, and notes the tool is an introspection stub (not fully functional). This adds important context beyond the schema, though more details on side effects or authorization would improve it.

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 sentences, each serving a purpose: first defines core action, second adds technical context. No filler, but the second sentence is somewhat jargon-heavy ('introspection stub') which may hinder clarity for some agents.

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 no output schema and moderate complexity (preview vs. apply, guarded write), the description omits expected responses, failure modes, permission requirements, and lifecycle details. The agent would struggle to use this tool effectively without external knowledge.

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 baseline is 3. The description adds minimal extra meaning beyond parameter descriptions (e.g., 'high-level desired changes' is vague). It does not significantly enhance understanding of parameter usage or constraints.

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 explicitly states 'Preview or update Sponsored Display campaign budgets', clearly identifying the action and resource. The '[Ads / guarded write]' prefix and 'Hosted endpoint only' distinguish it from sibling tools that may operate on other ad types or endpoints.

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 mentions preview vs. update and notes it's a stub, providing some context. However, it fails to explicitly state when to use this tool over siblings like update_campaign_budget or update_sb_campaign_budget, nor does it specify exclusions or prerequisites.

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