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

Adds substantial behavior beyond the annotations: everything is created PAUSED, so nothing spends until explicitly enabled, and the dry_run/confirm workflow is spelled out. The sales path requires a Pixel and event, and the leads path branches by destination, which tells the agent what side effects and prerequisites to expect from an openWorld write tool.

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?

Front-loads the core action, then layers goal, targeting and budget, and ends with the safety workflow — a sensible order with little filler. It is dense, and the goal sentence partially duplicates what the lead_destination schema description already enumerates.

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 34-parameter composite creation tool with no output schema, the description covers scope, the paused state, prerequisite IDs (pixel, form, identity, video) and the dry-run contract. It omits what is returned (campaign/ad group IDs) and how partial failures behave, which are the remaining gaps.

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 68%, and the description adds conceptual meaning on top: what 'automatic' vs 'manual' targeting covers, that budget can be daily or lifetime and live at campaign or ad group level, and how goal values constrain which other parameters matter. Some of this restates the schema's own enum descriptions (targeting, lead_destination), so it is additive but not fully novel.

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?

Opens with a specific verb and resource ('Create a complete TikTok campaign') and immediately scopes it: campaign + ad group, plus an ad when video_ids are given. This distinguishes it from tiktok_create_ad and from the sibling list/read tools without needing the schema.

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 explicit operational guidance: always call with dry_run=true first, show the plan, and require user confirmation before a real launch. It also routes goal choice (sales vs leads) to the required supporting inputs. It stops short of naming when to use tiktok_create_ad or tiktok_campaigns instead, so it is clear context rather than full when/when-not coverage.

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