list_friends

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 does disclose the returned fields (MID, status message), which is useful, but says nothing about whether the operation is read-only (only implied by 'list'), how many friends are returned, whether results are paginated or truncated, or whether auth is required.

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?

A single compact sentence that front-loads the verb and resource and adds the return payload without filler. Every clause earns its place.

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?

No output schema and no annotations, so the description must carry everything; it names the returned fields, which helps, but omits pagination/limit behavior and auth or permission requirements. Adequate but with clear gaps for a list endpoint that could return an unbounded set.

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 100% and the single optional 'search' parameter is documented in the schema (กรองชื่อเพื่อนที่มีคำนี้). The description adds no information about the filter syntax or matching behavior (partial vs exact, case sensitivity), so the baseline 3 applies.

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?

States a specific verb (ดึง = fetch) plus the resource (รายชื่อเพื่อนทั้งหมดในสมุดรายชื่อ LINE) and even names the returned fields (MID, status message). It is clear the agent can distinguish it from get_my_profile or rename_friend, though it never explicitly contrasts itself with sibling list tools such as list_chats.

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?

No when-to-use guidance, no prerequisites, and no mention of alternatives such as searching or filtering by other criteria. The agent must infer that this is the tool for enumerating contacts versus listing chats.

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