upload_audience_file

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

With no annotations provided, the description carries the full behavioral burden. It discloses file type/size limits, the requirement to provide file_base64, the fixed purpose, and the file_id return format, which gives the agent meaningful behavioral expectations beyond the schema.

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?

The description is three focused sentences with no filler. The core purpose and result are front-loaded, and the file-format and size constraints are stated efficiently.

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?

Despite no output schema, the description explains the return value and how to use it in downstream operations. It covers input format, size, purpose, and next steps, making it complete enough for a 4-parameter upload tool with no annotations.

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 75%, so the schema already documents three parameters clearly. The description adds some semantic context around file_base64 and the file's purpose, but it does not elaborate on ad_account_id, which lacks a schema description, leaving that parameter under-specified.

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 states a specific action ('Upload a file'), a clear resource ('custom audience creation'), and concrete constraints (CSV/TXT, up to 500MB). It also names the return value and downstream tools, making it distinct from siblings like upload_image and create_custom_audience.

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 clearly frames this as a preparatory step for create_custom_audience or add_audience_members, which gives the agent a solid when-to-use context. It does not explicitly exclude alternatives such as upload_image or create_partner_data_upload, so it falls short of full usage-guideline coverage.

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