Build LINE audience from user IDs

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

Beyond annotations (non-readOnly), the description reveals indexing delay (~5-10 min), status in list endpoint, user_id limit, and region restrictions. No contradictions.

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?

Concise, front-loaded with purpose, followed by timing, limits, region, return format, and example. No unnecessary words.

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?

Covers key aspects: purpose, behavior, limits, region, return format. With no output schema, it explains returns. Lacks prerequisites but acceptable.

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 high (75%). Description repeats user_ids limit and is_ifa usage, and adds region context for 'oa'. Does not add new parameter details beyond schema.

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 clearly states the tool creates a LINE audience by uploading user IDs or IFAs, specifically for the CSV-to-retargeting-audience flow. It distinguishes from sibling 'line_build_audience_from_engagement' by focusing on user IDs.

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?

Provides context on when to use (uploading IDs from CSV, retargeting), indexing time, and region gating. Lacks explicit contrast with siblings but is clear enough for an agent to infer.

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