create_character_4dir

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

With no annotations, the description carries full burden. It discloses persistence, return of character_id for later reuse, and directional views. It does not detail side effects, deletion, or rate limits, but the persistence aspect and reuse capability are clearly stated, which is sufficient for a creation tool.

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 only 4 sentences, all essential. It is front-loaded with the main action and resource, then quickly provides size, return value, and usage differentiation. No wasted words.

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?

Given the tool's complexity (13 params, no output schema), the description is fairly complete: it covers purpose, usage alternatives, return value, and key constraint (size). It does not explain the output format beyond character_id, but that is sufficient for context. Minor gap: could mention that the character is stored and can be listed/deleted.

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 100%, so the description does not need to restate parameter details. However, it adds no extra context beyond the size range already in the schema. Baseline 3 is appropriate as the description neither harms nor significantly enhances parameter meaning.

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 creates a persistent game character with 4 directional views, specifies size range (32-168px), and mentions the return of a character_id for reuse with animate_character. It effectively distinguishes from siblings by naming create_character_8dir for 8 directions and generate_image for one-off sprites.

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 explicitly says 'Use this for game characters that need multiple directions and animations' and provides direct alternatives: 'For 8 directions use create_character_8dir. For one-off sprites without persistence use generate_image.' This gives clear when-to-use and when-not-to-use guidance.

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