react_message

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

With no annotations provided, the description must carry the full burden of behavioral disclosure, but it only states the action without mentioning side effects, permission requirements, or how the reaction appears to others. It does not indicate whether the operation is reversible or what happens on failure, leaving the agent without critical behavioral context.

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 a single, compact sentence that immediately conveys the action. It is appropriately sized and front-loaded, containing no filler or repetition, and every word 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?

As a minimal one-liner with no output schema or annotations, the description omits essential context such as which messaging platform this applies to, how to format the emoji, and whether agent_id is needed for attribution. This leaves significant gaps that may lead to incorrect invocation.

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 input schema has three parameters (emoji, agent_id, message_id) with no descriptions, and the tool description does not elaborate on their meaning, format, or required values. Since schema description coverage is 0%, the description offers no compensatory detail for agents to understand how to correctly fill in these fields.

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 uses the specific verb 'Add' and clearly identifies the resource as 'an emoji reaction to a message,' distinguishing it from related tools like reply_message or post_message. The tool name react_message aligns perfectly with the description, leaving no ambiguity about the tool's core function.

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 provides no guidance on when to use this tool versus alternatives such as chat_say, reply_message, or post_message. There is no mention of prerequisites like needing an active chat or a valid message, nor any exclusions or preferred contexts.

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