Push Text Message

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

The destructiveHint annotation signals that pushing a message has irreversible side effects, but the description adds no behavioral context such as immediate delivery, inability to recall, or quota implications. It repeats the obvious action rather than disclosing consequences.

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?

Two short sentences, front-loaded with the action and followed by a usage condition. No filler or repetition.

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?

Adequate for a simple direct-message tool, but it leaves the destructive/side-effect nature unexplained and does not reference the broadcast/flex siblings even though the schema and annotations are otherwise thin. It is callable but not fully contextualized.

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?

The schema already documents that text is plain content and that userId defaults to DESTINATION_USER_ID; the description's 'simple text message without formatting' adds little. With only 50% schema description coverage and no extra parameter guidance in the description, the gap is not compensated.

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 states a specific action ('Push a simple text message to a user via LINE') and explicitly limits scope to plain text without formatting, which distinguishes it from sibling flex and broadcast tools. The resource, channel, and message type are all clear.

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 phrase 'Use this for sending plain text messages without formatting' gives clear conditions for use and implies it is not for rich content. It does not explicitly name alternative tools or state when not to use it, so it falls one step short of fully explicit guidance.

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