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

Annotations already declare readOnlyHint, openWorldHint, idempotentHint, and non-destructive behavior, so an agent knows this is a safe read. The description layers on the valuable addition that ids are 'live' (real-time) and that experimental/alias values are excluded, which affects result interpretation. The '24 canonical' count also sets accurate expectations. These details enrich—but don't fully transform—what annotations already convey, so not a 5.

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?

Three sentences deliver purpose, sequencing, exclusions, and filtering options with zero waste. The most critical information (what it lists) is front-loaded, and the sibling-tool reference is efficiently woven in. Every clause earns its place.

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 read-only list tool with 2 optional, fully-documented parameters, a present output schema, and complete safety annotations, this description covers all bases: what, when-to-call, exclusions, and how to filter. There is no missing information an agent would need to invoke it correctly.

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% with thorough type, enum, and description fields on both group and limit parameters. The description's 'Filter with group or limit when you only need one look' does add use-case framing beyond the schema, but the schema already carries the semantic weight. This aligns with the baseline-3 expectation when schema documentation is comprehensive.

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 opens with a specific verb and resource: 'List the 24 canonical Mangii art styles with live style ids.' This precisely scopes what the tool returns and is clearly distinct from its content-creation siblings. Mentioning 'Call this before manga.create_story' explicitly distinguishes it from a named sibling.

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 gives explicit when-to-use guidance: 'Call this before manga.create_story.' It also explains the exclusion of experimental and alias ids, setting expectations for output. It stops short of naming an alternative tool for when this one doesn't apply, but the sequencing mandate and filter hints provide solid directional context.

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