react_message

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

Annotations indicate mutation (readOnlyHint=false) but no destructiveness. The description adds valuable behavioral detail not in annotations: that an empty emoji string removes all reactions, and how 'big' and 'add_to_recent' modify behavior. This goes beyond what annotations provide.

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, front-loaded with the main purpose, and uses a clear docstring structure for parameters. Every sentence adds value without unnecessary verbosity.

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?

The tool has an output schema, so return format need not be described. The description covers key behavioral nuances (reaction removal, big animation, recent list) and is sufficient for a low-complexity action. Minor gaps like authorization or response details are acceptable given good annotations.

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 0%, so the description must compensate. It explains the emoji parameter format and special empty-string behavior, and describes 'big' and 'add_to_recent'. However, it does not explain 'chat' or 'message_id', though their purposes are fairly inferable from names.

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 begins with 'Поставить реакцию-эмодзи на сообщение' which clearly states the action (react) and the resource (message), distinguishing it from sibling tools like send_message or edit_message. It's specific and 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 clearly implies when to use: when you want to set an emoji reaction on a message. It doesn't explicitly mention alternatives or when not to use, but the context is clear enough given the tool name and sibling set.

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