get_follower_ids

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

The annotations include readOnlyHint=true, which already indicates a safe read operation. The description goes further by explaining the purpose (obtaining IDs for messaging) and implying the data is a list, which aligns with the read-only nature. It does not contradict annotations, and the additional context about the use case enhances transparency beyond the annotation.

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, with two sentences that directly state the tool's function and a key use case. It is front-loaded with the primary action ('Get a list of user IDs') and avoids unnecessary detail. Every word earns its place, making it easy for an agent to scan 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 the simplicity of the tool (few params, no output schema, read-only), the description is nearly complete. The main missing piece is the return format, but with no output schema and the schema already providing param descriptions, this is a minor gap. The description sufficiently explains the tool's role in the context of messaging, which is enough for an agent to use it correctly.

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 100%, so the schema already documents both parameters (limit and start). The description does not add syntax or format details beyond that. However, it does implicitly convey that the result is a list of IDs and that 'start' is a continuation token, which is already in the schema. The description adds little incremental meaning, so a baseline 3 is appropriate.

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 function: retrieving user IDs of friends who added the LINE Official Account, with a specific purpose (sending messages). This distinguishes it from sibling tools like get_profile (which retrieves a single user's profile) and the messaging tools (which send messages). The verb 'get' plus the resource 'follower IDs' makes the 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 implies usage for obtaining user IDs for messaging, but does not provide explicit when-to-use or when-not-to-use guidance, nor does it mention alternatives. Sibling tools like get_profile exist for retrieving individual profiles, but the description does not contrast them. The intended use case is clear enough for an agent to infer, but explicit routing is missing.

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