Get LINE User Profile

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

Annotations already indicate readOnly, non-destructive, and idempotent behavior. The description adds valuable context: the exact preconditions for success (friend, not blocked, consent) and the ambiguous 404 handling with a Thai explanation. This goes beyond the annotations by detailing failure modes and error messaging.

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 concise, well-structured with paragraphs, Args, and Returns sections. Every sentence provides essential information without fluff, making it easy for an agent to parse quickly.

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?

Given that the input schema has 3 parameters with some descriptions, no output schema, and annotations present, the description covers all necessary context: usage conditions, error behavior, return structure, and parameter hints. It is complete for a simple fetch 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 description coverage is low (33%), but the description adds meaning: for user_id, it specifies 'typically starts with U'; for oa, 'optional OA id'; for response_format, it confirms the default and enum, mostly redundant with schema. It partially compensates for the coverage gap but doesn't fully explain all parameter semantics.

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 it fetches a LINE user's profile including specific fields (display name, picture, status message, language) by user ID. It distinguishes this tool from sibling tools like line_get_oa_status, which focus on OA status, making its purpose unambiguous.

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 explicitly states when the tool works: only if the user added the bot as a friend, hasn't blocked it, and consented to share profile. It also mentions the ambiguous 404 error and the Thai-language explanation. While it doesn't provide exclusion criteria or alternatives, the conditions are clear and sufficient for proper usage.

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