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

Annotations already declare readOnlyHint=false and destructiveHint=true, so the safety profile is carried by structured data. The description adds useful scoping (geo is set per channel and only these two channels carry it) but does not disclose the replace-vs-omit semantics, which live only in the schema parameter descriptions, nor what happens to prior targeting.

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?

Only two sentences and the core action is front-loaded, but the second sentence is a dangling fragment missing its verb ('which countries/states the campaign serves in...'), which slightly obscures rather than tightens the message.

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 5-parameter destructive mutation with no output schema, the description covers purpose and scope but is silent on return/confirmation behavior and on preconditions (e.g., whether the campaign must be unlaunched), leaving the agent to infer whether the call is a one-shot overwrite.

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% and the parameter descriptions are unusually rich (REPLACES / [] to clear / omit to leave unchanged / US states only / country-level exclusions only). The description adds nothing beyond that, so the 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 specific verb and resource: set geographic targeting on a wizard campaign's search channel, limited to Google Ads or Microsoft Ads, covering included countries/states and excluded countries. It's clear enough to distinguish from generic campaign tools, but it never names the natural read counterpart (get_campaign_targeting_locations), so sibling differentiation is only implied.

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?

Usage is implied by the scope statement (per-channel geo on wizard campaigns) but there is no explicit when-to-use/when-not, no mention of checking existing targeting first via get_campaign_targeting_locations, and no prerequisite context such as campaign launch state.

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