discord_add_reaction

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

With no annotations provided, the description carries the full burden of behavioral disclosure. While 'Adds' implies a mutation operation, it doesn't disclose important behavioral traits: whether this requires specific permissions, rate limits, whether reactions are idempotent (can you react multiple times with the same emoji?), or what happens on success/failure. For a mutation tool with zero annotation coverage, this leaves significant gaps.

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 extremely concise at just 7 words, front-loading the core purpose with zero wasted words. Every element ('Adds', 'emoji reaction', 'specific Discord message') earns its place by contributing essential information about the tool's function.

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 mutation tool with 3 parameters, 0% schema description coverage, no annotations, and no output schema, the description is insufficiently complete. It doesn't explain the expected parameter formats, authentication requirements, error conditions, or what constitutes a successful reaction addition. The agent would need to guess about many operational aspects when invoking this tool.

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 description mentions 'emoji' and 'specific Discord message' which partially explains the purpose of the parameters, but with 0% schema description coverage and 3 undocumented parameters, it doesn't adequately compensate. It doesn't explain what format 'emoji' should be in (Unicode vs custom emoji ID), or that 'channelId' and 'messageId' are Discord snowflake identifiers. The baseline is 3 because the schema coverage is 0%, but the description adds only minimal value.

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 ('Adds an emoji reaction') and target ('to a specific Discord message'), providing a specific verb+resource combination. However, it doesn't explicitly differentiate from its sibling 'discord_remove_reaction' beyond the obvious verb difference, missing an opportunity to clarify the relationship between these complementary tools.

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. It doesn't mention when to choose 'discord_add_reaction' over 'discord_add_multiple_reactions' (for bulk operations) or 'discord_send' (for creating messages rather than reacting to them). There's also no mention of prerequisites like authentication or channel access requirements.

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