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

Annotations only declare non-read-only, non-destructive, open-world. The description adds real behavior: the squad is created PAUSED so nothing spends, pixel goals auto-resolve to the account pixel unless pixel_id is given, and dry_run can be used as a pre-flight check. It stops short of saying what dry_run actually returns or whether the response includes the new ad squad ID.

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?

Three dense sentences, front-loaded with the action and its default state, then targeting, then the dry_run recommendation. The parenthetical enumerations are compact and each carries distinct information.

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 16-parameter mutation tool with a nested targeting object and no output schema, the description covers the highest-risk semantics (PAUSED creation, targeting precedence, pixel resolution). The remaining gap is that it never describes what a successful call returns or how the created squad is identified.

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?

With 56% schema coverage across 16 params, the description earns credit for decomposing the untyped `targeting` object into geos/demographics/devices/segments and for stating that budget and bid are in account currency and that pixel_id is only needed to override the default. Start_time, end_time, folder, language, and name remain undocumented in both places.

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 precise verb+resource+parent ('Create an ad squad (PAUSED) inside a campaign') and enumerates the dimensions it controls (goal, budget, bid strategy, targeting, placements). The default PAUSED state and the 'inside a campaign' containment cleanly separate it from snapchat_create_campaign and snapchat_launch_campaign.

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 a concrete recommended workflow ('Offer dry_run=true first') and explains the two targeting paths (copy_targeting_from vs an inline Snap targeting object). It does not state when to prefer this over snapchat_launch_campaign or snapchat_duplicate, so routing between creation tools is left partly to inference.

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