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

The description adds minimal behavioral context beyond the annotations. 'Inspect' aligns with readOnlyHint=true and destructiveHint=false. The mention of 'ordered reference-image set' hints at the output structure, but no further details about auth, rate limits, or idempotency are provided. Annotations already cover the safety profile.

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?

A single sentence of 14 words that is front-loaded and efficient. However, it is slightly terse and could be more explicit about the core resource (e.g., 'Reusable character' is a domain term that may not be universally understood). Still, it earns its place without excess.

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 simple nature of the tool (read a single character), the presence of annotations and an output schema, the description is mostly complete. It clarifies the use case and the ordered reference-image set. However, it does not explicitly state that the characterId is required or that the operation is read-only, though these are inferred from context and annotations.

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 does not mention any parameters. Schema coverage is 50% (workspaceId has a description in the schema, but characterId does not). The tool description could have explained what characterId represents, but it fails to compensate for the undocumented parameter, leaving a gap.

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 specifies the verb 'Inspect' (read-only) and the resource 'one reusable character and its ordered reference-image set', with a clear scope ('before planning a story'). This distinguishes it from siblings like 'characters_list' (list all) and 'characters_apply' (apply a 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 provides a clear context for when to use this tool ('before planning a story'), but does not explicitly mention when not to use it or alternatives such as 'characters_list' for browsing. The sibling list implies the differentiation, but the description could be more direct.

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