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

The description extensively explains behavioral aspects: the animationQualityGate semantics, collision detection rules, normalization of bodies, and URL expiration. It also notes that the payload matches the in-app preview, ensuring consistency. These details go beyond the annotations and provide a thorough understanding of the tool's output behavior.

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 overly long and repetitive, with redundant explanations about collision and normalization (e.g., 'Bodies are normalized...' appears once, but the point about not subtracting offsets is repeatedly stressed). The structure is a single dense paragraph, making it harder to scan. It could be significantly tightened without losing information.

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?

The description provides rich context for interpreting the returned data, including quality gates, collision handling, and URL expiry. It covers the main complexities of the payload. However, it does not address potential error conditions or what happens if the character does not exist, which might be relevant for a getter. Overall, it is fairly complete given the tool's purpose.

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 only parameter, characterId, is described minimally as 'Character id.' The schema already provides the type and name, so the description adds little extra meaning. Since the parameter is straightforward, the baseline of 3 is appropriate.

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 indicates that the tool returns the full PhaserCharacter JSON, including animations, poses, and other data. It is distinct from sibling getter tools by focusing on character-specific data. However, it does not explicitly state the action 'fetch' or 'retrieve', relying on the name 'get_character'.

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 by detailing the payload structure, but it does not explicitly compare with alternatives like get_asset or list_characters. It lacks clear guidance on when to choose this tool over others, though the focus on character specifics provides some hint.

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