Send a text message to a LINE user, group, or room by providing a recipient ID and message content.
Send a text message to a LINE user, group, or room.
| Name | Required | Description | Default |
|---|---|---|---|
| to | Yes | User ID, group ID, or room ID | |
| message | Yes | ||
| channel_access_token | No |
Changes observed during successful MCP inspections.
v0.1.11Input schema / requiredPrevious value: -[
- "channel_access_token",
- "to",
- "message"
-]New value: +[
+ "to",
+ "message"
+]v0.1.5Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description carries the full burden. It says nothing about authentication (channel access token), messaging-quota/rate limits, whether delivery is push-based and counts against the monthly allowance, or what errors look like on invalid IDs — all material for a write tool.
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 front-loaded sentence with no filler, which is efficient. However, the brevity tips into under-specification for a messaging tool with an auth parameter rather than achieving well-judged density.
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?
With no annotations, no output schema, and two of three parameters undocumented, this one-liner leaves out essentials: token requirements, message length/format constraints, and the difference between push and reply/broadcast semantics. An agent could call it, but not confidently or correctly on first attempt.
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 only 33%, and the description does not compensate: the undocumented channel_access_token parameter is never mentioned, nor is how a token is obtained or whether it is required versus ambient. The one clarification it does offer (user/group/room targets) merely restates the 'to' field description.
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 (send) and resource (text message) plus the target types (user, group, room). It implicitly distinguishes itself from line_send_flex_message and line_broadcast via 'text' and the direct-target framing, but never names those siblings explicitly.
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 guidance on when to use push-send versus line_reply_message (reply token flows) or line_broadcast (fan-out). The agent must infer the choice from sibling names alone; nothing in the description states prerequisites or exclusions.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.