discord_add_reaction

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

Annotations already indicate this is a write operation (readOnlyHint=false) and not destructive (destructiveHint=false). The description adds the local configuration requirement ('Writes must be enabled locally') and notes the bot as the actor, which is useful context. However, it doesn't disclose additional behaviors like error handling, rate limits, or idempotency details beyond what the annotations provide. This is adequate but not rich.

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 two short sentences that lead with the core action, followed by a key prerequisite. Every word earns its place, with no redundancy or filler. It is perfectly sized for a simple tool.

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 mutation tool, the description covers the primary purpose and a critical local configuration requirement. The annotations handle safety traits (readOnly, destructive) and idempotency. However, it doesn't mention edge cases like duplicate reactions, emoji format details, or error scenarios. Given the tool's simplicity and the annotation coverage, it's sufficiently complete for an AI agent, though not exhaustive.

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 only describes the 'emoji' parameter (33% coverage), leaving channelId and messageId undefined. The description does not compensate for this gap—it says nothing about what these parameters mean or how they relate to the target message. For a low-coverage schema, the description should clarify parameter semantics, but it doesn't add any value beyond the schema.

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 action: 'Add a reaction as the configured bot.' It specifies a verb ('Add') and a resource ('reaction'), and the 'configured bot' context distinguishes it from general Discord operations. This is unambiguous and distinct from sibling tools like sending messages or admin actions.

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 a prerequisite ('Writes must be enabled locally') but gives no guidance on when to use this tool versus alternatives. It doesn't mention scenarios where adding a reaction is appropriate or how it differs from discord_send_message or admin tools. No explicit or implicit usage context is provided beyond the action itself.

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