campaign_report

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

Annotations already declare readOnlyHint, idempotentHint, and openWorldHint, so the safety profile is covered. The description adds almost nothing beyond that: "Read" restates readOnlyHint, and "bounded" merely echoes the pagination schema's "bounded result window" without explaining truncation, rate limits, or auth/profile requirements.

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?

A single six-word sentence with zero filler and the key scope word up front. It borders on under-specification for a 9-parameter reporting tool rather than being wasteful, but nothing needs to be trimmed.

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?

An output schema exists and the input schema is fully documented plus annotations cover safety, so the description does not need to explain return values. Still, for a report tool with nine parameters and many report siblings, the absence of any selection or scope context leaves a real gap.

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 description coverage is 100% across all 9 parameters (fields, filters, groupBy, options, timeRange, sorting, pagination, profile, adAccountId), so the schema carries full parameter meaning. The description supplies no additional semantics such as which fields are valid or how timeRange interacts with granularity, so baseline 3 applies.

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 clear verb and resource ("Read ... campaign performance rows") so an agent knows it is a reporting/read tool at campaign scope. However, it never distinguishes itself from the many sibling report tools (ad_report, ad_group_report, keyword_report, search_term_report), so the campaign-level boundary is inferred only from the name.

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?

No when-to-use guidance, no prerequisites (profile, ad account), and no mention of when to prefer it over the other report siblings. The only cue is the tool name itself.

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