Add reaction

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

No annotations are provided, so the description must fully disclose behavior. It only states the basic action and emoji types. Missing details like required permissions (e.g., 'Add Reactions'), rate limits, confirmation of success, or behavior when emoji is invalid. For a tool that mutates state, this is insufficient.

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 concise sentence that immediately states the action and key details. Every word is purposeful with no fluff. It is front-loaded and efficient.

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?

For a simple reaction tool, the description covers the main functionality. However, it lacks context on error handling (e.g., missing permissions, invalid emoji), idempotency (can the same reaction be added twice?), and return behavior. Given no output schema, more guidance would improve completeness.

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 already has detailed descriptions for all parameters (100% coverage). The description adds value by clarifying emoji formats (Unicode vs custom name/id) and explaining the optionality of 'server' under certain conditions. This goes beyond the schema's basic descriptions.

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 clearly states the tool adds a reaction to a message with either a Unicode emoji or a custom guild emoji, specifying the format (name/id). It distinguishes from siblings like 'remove_reaction' and 'get_reactions' by focusing on the add action.

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 implies usage for adding reactions but provides no explicit when-to-use or when-not-to-use guidance. It does not mention alternatives like 'remove_reaction' for removal, though the sibling list includes it. The context is clear enough for basic selection.

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