Create emoji

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

Annotations indicate this is not read-only and not destructive, which aligns with creation. The description adds behavioral details: file size limit (256 KB) and supported formats (png, jpeg, gif, webp). However, it does not disclose required permissions, failure modes, or side effects (e.g., overwriting existing emoji with same name). Some useful context is provided, but gaps remain.

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: two sentences, no redundant words. The first sentence states purpose, the second adds critical constraints. 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 creation tool, the description covers the core action and a key limitation. However, it lacks context on what happens after successful upload (e.g., return value), behavior of the optional 'guild' parameter (defaults explained in schema but not in description), and error handling for invalid URLs or oversized files. Adequate but not thorough.

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 coverage is low (33%: only guild has a description). The description does not compensate for the missing semantics of 'name' and 'image_url'. It mentions image URL but does not explain constraints (e.g., validity, resolution) or name rules (alphanumeric, length). The agent would benefit from clearer parameter explanations.

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: 'Upload a custom emoji from an image URL.' It specifies the verb (upload), resource (custom emoji), and source (image URL). This is distinct from sibling tools like delete_emoji or update_emoji, making the purpose unmistakable.

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 creating emojis but offers no explicit guidance on when to use this tool versus alternatives (e.g., update_emoji). It provides constraints (file size, formats) but no comparison with siblings or conditions for avoidance.

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