Build LINE audience from user IDs

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

The description discloses indexing time (~5-10 minutes) and status progression, adding to the annotations. No contradictions with annotations.

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 well-structured with Args and Returns sections, concise but informative. Slight redundancy in region note could be integrated.

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 creation, indexing delay, region gating, and provides an example. Despite no output schema, the return format is described, making it complete for this tool.

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%; description adds context for parameters (e.g., name max 120 chars, user_ids max 10k, is_ifa default false) and explains the return object, enhancing the 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 new LINE audience by uploading user IDs or IFAs, differentiating it from siblings like line_build_audience_from_engagement which uses engagement data.

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 provides context for Thai SMBs and mentions the typical use case, but does not explicitly state when not to use or mention alternatives like line_build_audience_from_engagement.

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